Plant Breeding Institute, The University of Sydney, Sydney, Australia

Screening of Chickpeas for Adaptation to Autumn Sowing

N. O'Toole, F. L. Stoddard and L. O'Brien

Authors' addresses: Dr N. O'Toole and Dr L. O'Brien, Plant Breeding Institute, PO Box 219, Narrabri, NSW 2390, Australia;Dr F. L. Stoddard (corresponding author), School of Applied Sciences, University of Wolverhampton, Wulfruna Street,Wolverhampton WV1 1SB, UK

With 6 ®gures and 9 tables

Received September 11, 2000; accepted January 4, 2001

Abstract

Dry matter accumulation was determined in 27 chickpea(Cicer arietinum) lines in time-of-sowing ®eld trials and incontrolled-environment chambers at day/night tempera-tures of 13/5, 18/8 and 23/13 °C to assess tolerance togrowth-inhibiting temperatures. Field trials were based atNarrabri, NSW, Australia, in a region of summer-domin-ant rainfall where winter crops are grown on stored soilmoisture. Percentage emergence was lower than expected insome ®eld trials and in the coolest controlled environment.Subsequent dry matter accumulation showed the e�ects ofpoor crop establishment until the onset of ¯owering.Kabuli types were more susceptible to poor emergencethan desi types. Di�erent lines yielded the greatest drymatter production at di�erent stages of growth. In theseedling phase, to 30 days after emergence, kabuli acces-sions SP1.563 and Garnet showed signi®cantly greater drymatter accumulation than all other accessions in allcontrolled environments, suggesting broad adaptation.One desi accession, Gully, was almost as productive asthese two kabuli accessions in the intermediate environ-ment but was much poorer in the other environments,indicating very narrow adaptation. In the vegetative phase,the greatest relative growth rates were found in the desiaccessions. Line 940-26 was identi®ed as highly productivein both ®eld and controlled-environment experiments. Drymatter accumulation was not signi®cantly a�ected bytemperature, although it was slightly greater in the coolestcontrolled environment than in the other two. The acces-sion by temperature interaction was not signi®cant, show-ing that the breadth of adaptation was similar in allaccessions during this growth phase. The optimum time ofsowing for dry matter accumulation was late May, 4±6weeks before the winter solstice. The results showed thatchickpeas are well adapted to germination and seedlingestablishment in moderate conditions, followed by veget-ative growth in cooler conditions. These conditions aretypical following autumn sowing in a Mediterranean ortemperate environment. Kabuli types appear to havestronger growth during the seedling phase and desi typesduring the vegetative phase. Recombination of these traitscould lead to more productive cultivars.

Key words: Cicer arietinum Ð cold tolerance Ðdry matter accumulation

Introduction

Chickpea (Cicer arietinum L.) is increasingly beingsown in the autumn rather than the spring. Thelonger growing season potentially brings signi®-cantly greater yield in appropriate cultivars(Keatinge and Cooper 1983, Singh et al. 1994).Much of the investigation of potential adaptationof chickpea to autumn sowing has been done inwinter-rainfall Mediterranean-type environments(e.g. Siddique et al. 1999). In these environments,chickpea crops sown earlier accumulated morebiomass and produced a higher grain yield (Saxena1981, Siddique and Sedgley 1986), although in otherexperiments a later sowing was required for maxi-mum grain yield than for maximum biomass (Sinha1983, Horn et al. 1996, Armstrong et al. 1997, Dalalet al. 1997).There is also potential to grow this crop on

stored moisture in summer-rainfall dominant, tem-perate environments, such as that of northern NewSouth Wales, Australia. This substantially di�erentenvironment requires further de®nition of theoptimal time of sowing.An understanding of cold tolerance is important

for the adaptation of chickpea crops to theseconditions. Autumn-sown crops are often subjectedto temperatures below the optimal range of 20 to35 °C during emergence (Ellis et al. 1986, vanRheenen et al. 1991), early growth (Khanna-Chopra and Sinha 1987) and pod set (Siddiqueand Sedgley 1986). The in¯uence of temperature ongrowth and development varies with genotype andstage of growth (Singh et al. 1981, Khanna-Chopra

J. Agronomy & Crop Science 186, 193Ð207 (2001)Ó 2001 Blackwell Wissenschafts-Verlag, BerlinISSN 0931-2250

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and Sinha 1987, Singh et al. 1989, Malhotra et al.1990, Singh et al. 1995). By measuring the e�ectsof di�ering temperatures on emergence, seedlinggrowth and biomass accumulation in vegetativeplants grown in controlled conditions, limitationsto ®eld growth can be identi®ed or con®rmed.The ®rst experiment was therefore designed to

investigate the e�ects of time of sowing, in autumn,on dry matter accumulation in a range of chickpeagermplasms. The experimental site was in thesummer-rainfall belt of northern New South Wales,where crops are grown through the winter onstored soil moisture. Two experiments, on seedlingsup to 30 days old and vegetative plants 30±70 daysold, were subsequently undertaken using controlledenvironments to test the e�ects of temperature onthe same range of germplasms.

Materials and Methods

Seed material

Twenty-seven accessions (Table 1) were used in these experi-ments. Theywere chosen to include desi and kabuli types andto represent commercial cultivars, advanced breeding linesand direct introductions from a range of sources. Two ofthese lines, 8838-4H and 8818-45H, were derived from ®rstbackcrosses of Cicer reticulatum to C. arietinum and twoother lines, 8949-46F6 and 8950-18F6, were derived fromcrosses of C. echinospermum to C. arietinum. CultivarsLasseter and Tyson were used only for controlled-environ-ment experiments and breeding lines T2200, 8818-45H andT1210 were used only for ®eld experiments.

Seed viability was estimated by germinating 100 ran-domly selected seeds of each accession for 14 days at 25 °C.The combination of percentage germination and 100-seedweight was used to estimate the seed requirements toestablish crop densities of 40 plants m±2. In 1995 and 1996,this estimate was further corrected for the emergenceobserved at the same time of sowing in the previous year.

Two weeks before sowing, seeds for ®eld experimentswere dressed with the fungicide thiram (AmalgamatedChemicals, Homebush Bay, NSW, Australia) at the rate of2 g kg±1 of seed to minimize loss of seedlings to Phyto-phthora and Pythium during early seedling growth. Imme-diately prior to sowing, all seeds were inoculated with anexcess of rhizobium Group N (Nitro-plusÒ, Bio-Care,Somersby, NSW, Australia). Several plants from the bu�errows were removed 3 weeks after plant establishment tocon®rm that nodulation had occurred.

Field experiments

The ®eld experiments were conducted at the University ofSydney, Plant Breeding Institute, Narrabri, NSW, Australia(30°S, 150°E) in the winter cropping seasons of 1994, 1995and 1996. The soil type for all trial sites was a black

cracking clay Ug 5.2 (Northcote 1979). Temperature andrainfall were recorded during the three growing seasonsusing an automated weather station.

Each year, the trial site was prepared by disk ploughingand then harrowing twice to incorporate residue barleystubble from the previous year's crop. Herbicides wereapplied in early March, cyanazine (BladexÒ, Shell, Mel-bourne, Australia) at 3 l ha±1 in 1994, metribuzin (SencorÒ,Bayer, Pymble, NSW, Australia) at 435 ml ha±1 in 1995and glyphosate (Roundup CTÒ, Monsanto, Melbourne,Australia) at 800 ml ha±1 in 1996. In all years, persistentweeds were removed manually.

Soil tests were carried out to assess availability of soilnutrients, allowing for the addition of supplemental fertil-izer as required. Nitrogen in the form of anhydrousammonia gas was applied in early March at the rate of100, 100 and 75 kg N ha±1, respectively, in the three years.In 1996, zinc sulphate was applied at the rate of 10 kg ha±1

prior to sowing, as soil tests had established that zinc levelswere limiting.

Table 1: Accessions used in time of sowing experimentsin 1994, 1995 and 1996

Accession Description

DesiAmethyst Australian cultivarBarwon Australian cultivarCA1030 Introduction from IndiaDesavic Australian cultivarDooen Australian cultivarGully Australian cultivarLasseter Australian cultivarNorwin Australian cultivarSemsen Australian cultivarTyson Australian cultivarT1850 Introduction from IranT2200 Introduction from Iran8803-7H Australian breeding line8810-72H Australian breeding line8818-45H Breeding line from C. reticulatum/

2´ C. arietinum8838-4H Breeding line from C. reticulatum/

2´ C. arietinum8949-46F6 Breeding line from C. arietinum/

C. echinospermum8950-18F6 Breeding line from C. arietinum/

C. echinospermum940-26 Australian breeding lineKabuliBumper Australian cultivarGarnet Australian cultivarL550 Introduction from USAMission Introduction from USANarayen Introduction from former USSRSP1.563 Introduction from SpainT1210 Introduction from SpainUC5 Introduction from USA

194 O'Toole et al.

In 1994, the sowing dates were 26 May and 10 June.Each trial was designed as a randomized complete blockdesign with three replications. Plots were 7 m in lengthand contained four rows, with 50 cm between rows withinplots and 70 cm between plots. Supplementary irrigationwas applied four times using an Upton travelling irrigator,twice before sowing on 28 April and 18 May with thetotal equivalent of 137.5 mm of rain to ensure adequatemoisture in the soil pro®le, and subsequently on 15 Julyand 29 August, with the equivalent of 75 mm of rain eachtime. In September, crop monitoring indicated Heli-coverpa larvae at levels greater than the economic thresh-old level of 0.5 larvae m±2, so the trials were sprayed with2.1 l ha±1 of endosulfan (Nufarm, Laverton North, Vic.,Australia), on 3 and 26 September, which reduced thenumber of larvae to manageable levels.

The 1995 trial was planted on 10 May, 29 May and 14June. At each time of sowing, the trial was planted as alattice design with three replicates. The plot length for the10 May sowing was 6 m, while 9-m plots were sown on 29May and 14 June. Each plot consisted of seven rows spaced25 cm apart within plots with 70 cm between the outsiderows of adjacent plots. Five applications of endosulfan atthe rate of 2.1 l ha±1 were required at 10-day intervals from5 September to 15 October to limit aphid numbers in anattempt to reduce the transmission of viruses.

In 1996, the sowing dates were 14 May, 24 May and 12June. All trials were randomized complete block designswith three replications. Plot length was 8 m with 25 cmbetween rows and 70 cm between plots. On 7 and 25September, endosulfan at 2.1 l ha±1 was applied to the cropto minimize aphid numbers and reduce the potential spreadof aphid-borne viruses.

Emergence counts were taken 2 weeks after sowing andrepeated every 4 days until a constant value was achieved.Dry matter estimations for each plot were made 4 and 8weeks after constant emergence had been reached and atthe onset of ¯owering, except in 1994 when the 4-weekcollection was omitted. In 1994, six randomly selectedplants were removed from each plot at ground level. In1995 and 1996, 0.75 m2 of plant biomass was removed atground level, with the position of sampling being randomlyselected within the plot, and the site of the dry matterestimation was more than 50 cm from either end of the plotor any previous dry matter estimation. The plants wereweighed within 5 min of harvesting and dried at 80 °C untila constant weight was reached. Plant height was measuredas the perpendicular distance from ground level to theundisturbed top of the canopy, and canopy width was thehorizontal distance between the canopy edges of a singlerow of plants. Dry matter was estimated using a MosaicPasture Probe (Mosaic Systems Ltd, Palmerston North,New Zealand), which measures a change in the electroniccapacity between two conductors, the central spike and thesurface of the probe, brought about by plant biomass inclose proximity to the surface of the probe. At maturity,plots were harvested in a single direction with a Winter-steiger small plot harvester (Wintersteiger, Ried, Austria)and grain yield was determined.

Controlled-environment chambers

The potting mix was prepared in batches consisting of 20 lof peat moss, 30 l of sand, 1 kg of lime, 0.4 kg of dolomiteand 0.3 kg of fertilizer (500 g of superphosphate, 500 g ofdolomite, 200 g of lime, 220 g of gypsum, 60 g of K2SO4,and 120 g of KNO3).

Three temperature regimes were selected to cover theenvironmental range measured under ®eld conditions at thePlant Breeding Institute, Narrabri. Each growth chamber(ThermolineÒ, Smith®eld, NSW, Australia) was set to oneof the following day/night temperature regimes: 13/5, 18/8and 23/12 °C, with a photoperiod and temperature regimeof 12/12 h and a light intensity of 600 l Einsteins m±2 at thetop of the plants.

Ten accessions, namely Amethyst, Barwon, Desavic,Gully, Lasseter, 8803-7H, 8950-18F6 (desi), Garnet, L550and SP1.563 (kabuli), were used in the seedling experi-ment. Potting mix was placed to a depth of 6 cm in eachseedling tray (38 cm ´ 29 cm ´ 12 cm) and allowed toequilibrate to the temperature of the growth chamberovernight. Within each growth chamber, six trays wereplaced in a randomized complete block design. Each traycontained 15 seeds of each accession. The distancebetween rows was 2.5 cm, with 3.5 cm between theoutermost rows and the side of the tray. Within eachrow, seeds were placed every 1.2 cm, with 1.6 cm betweenthe last seed and the edge of the tray. Seeds were coveredwith 2 cm of equilibrated soil and trays were wateredevery third day to runo�. At 10 days after sowing,seedlings were counted as emerged if plant material wasvisible at ground level. Dry matter estimations were takenat 10, 20 and 30 days after sowing by the removal of one-third of emerged seedlings at ground level from eachaccession within each replicate. Freshly cut seedlings wereshaken to remove loose soil material. Samples weredehydrated at 80 °C until a constant weight. For eachaccession at each sampling, the number of harvestedseedlings was recorded to account for variations inemergence. All weights were standardized to an equivalentof 10 seedlings for each harvest prior to data analysis.

Twenty-four accessions were used in the vegetative phaseexperiment. For each accession, 10 150-mm squat pots(Yates, Sydney, Australia) were ®lled with potting mix. Ineach pot, four seeds were sown at a depth of 2 cm. The potswere placed in a glasshouse set at a constant temperature of22 °C at the University of Sydney. Accessions wererandomly distributed throughout the glasshouse, with the10 pots of each being arranged in blocks. Two weeks aftersowing, the seedlings in each pot were thinned to the mostuniform three. The pots remained in the glasshouse untiltransfer to the growth chambers at 30 days after sowingand were watered as required. Prior to transfer, the leastuniform of the 10 pots was eliminated and the remainingnine pots were randomly assigned to the three di�erenttemperature regimes. Within each temperature regime, thedesign consisted of a randomized complete block with threereplicates of the 24 accessions. Pots were watered everysecond day to run-o�, with an application of 0.2 gAquasolÒ soluble fertilizer (Hortico, Laverton North,

Temperature E�ects on Chickpea Growth 195

Victoria, Australia) per pot per week. Immediately prior tothe initiation of di�erential temperature regimes, a plantfrom each pot was removed at ground level for the initialestimate of biomass accumulation. After 20 days ofexposure to the temperature regimes, one of the remainingtwo plants in each pot was removed at ground level and theremaining plant was harvested after 40 days.

Statistical analysis

Field data were subjected to analysis of variance andgeneralized linear modelling using SuperAnova version1.11 (Abacus Concepts Inc., Berkeley, CA). Genotypic andphenotypic correlations were calculated using Data Desk4.2 (Data Description Inc., Ithaca, NY). Crop establish-ment was poor in the third replicate of the mid-June sowingin 1996, so this e�ect was reduced using nearest-neighbouranalysis in Mstatc 2.10 (Michigan State University, EastLansing, MI) with the adjusted data being reanalysed inSuperAnova.

In the controlled-environment experiments, emergencedata were not normally distributed so the arc sine squareroot transformation was applied. Seedling dry mattersrequired a log transformation. Vegetative phase dry matterdata at each time of harvest were normally distributed, butfor repeated measures analysis on all harvests, log trans-formation was required. Analysis of variance was under-taken using Minitab release 10.2 (State College, PA) andSuperAnova version 1.11 (Abacus Concepts Inc., Berkeley,CA). Growth rate was calculated as the weight at the laterdate divided by the weight at the earlier date for the 10±20and 20±30 day intervals in the seedling experiment and the0±20 and 20±40 day intervals in the vegetative phaseexperiment. No transformation was necessary to normalizethese data. Dry matter and relative growth rate data werealso analysed by a repeated measures model in eachexperiment. Correlation coe�cients were calculated usingaccession means across all environments (genotypic corre-lations) and accession means within each environment(phenotypic correlations).

Results

Field experiment

In most of the trials, 37±41 plants m±2 emerged,close to the target 40 plants m±2. In both sowings in1994, however, only 25±28 plants m±2 emerged,and in the ®rst sowing in 1996, 32 plants m±2

emerged. Kabuli types had particularly poor emer-gence in 1994. Apparently the pre-planting labor-atory-based germination tests undertaken in 1994did not adequately predict ®eld emergence.Dry matter production at 4 weeks after emer-

gence and at the onset of ¯owering was a�ected byyear, time of sowing and the interaction, while at8 weeks after emergence only the main e�ectswere signi®cant (Table 2). At 4 weeks, dry matter

production was especially low in the late May 1996sowing (Table 3), but it recovered, and this envi-ronment was associated with the highest dry matteryields at the subsequent two harvests. In ®ve of theeight comparisons, the late May sowing was asso-ciated with higher dry matter production thaneither the early May or early June sowing(Table 3).Accessions varied in dry matter production at all

times of evaluation (Table 2). In addition, severalof the accession ´ environment interaction termswere signi®cant. Some of this variation was attrib-utable to poor plant establishment, as shown by thee�ect of including the emergence as a covariate.Because of the signi®cant e�ects of environment onemergence, this covariate was ®tted as a set ofdi�erent lines (i.e. an interaction term) rather thanas a single line. Thus, di�erent slopes were providedfor each environment. This showed that there was asigni®cant and positive correlation with a slope of0.0118 (0.0033 S.E.) t ha±1 (plant m±2)±1 betweenemergence and dry matter yield at 4 weeks in theearly May and June sowings in 1996, but the othercorrelations were not signi®cant. At 8 weeks andagain at the onset of ¯owering, the e�ect ofemergence on dry matter remained signi®cant onlyin the 1994 sowings, where the variation in emer-gence had been greatest. The slopes of theseregressions were 0.0139 (0.0025 S.E.) at 8 weeksand 0.0185 (0.0031 S.E.) at the onset of ¯owering.Fitting emergence as a covariate increased theapportioning of sum of squares to the accessionterm and decreased apportioning to all of the year´ environment and residual terms in the generalizedlinear models at each harvest, except for the year ´time of sowing ´ accession term at 4 weeks(Table 2). Thus much of the genotype±environ-ment interaction was attributable to the after-e�ects of poor germination.No accession was consistently outstanding in dry

matter production across times and environments(Fig. 1). The greatest mean dry matter yield at 4weeks was found in the desi cultivar Barwon(Fig. 2). At 8 weeks, this cultivar had been passedby Mission (kabuli), 940-26 and Dooen (desi). Atthe onset of ¯owering, the highest dry matter yieldswere found in desi line 8838-4H. It is clear fromFig. 2 that some lines such as Dooen and Garnetstarted well but failed to maintain their advantageabove average, whereas other lines, most notably8949-F6, started poorly and made later gains.Other variates, namely plant height, canopy

width and indirect assessment of dry matter with

196 O'Toole et al.

Table

2:Analysisofvariance

andcovariance

ofdry

matter,relativegrowth

rate

andgrain

yield

(alllogtransform

ed),withem

ergence

asthecovariate

Dry

matter

Relativegrowth

rate

4weeks

8weeks

Onsetof¯owering

Weeks4±8

Week8to

onset

of¯owering

Grain

yield

Sourceofvariation

d.f.

Mean

square

d.f.

Mean

square

d.f.

Mean

square

d.f.

Mean

square

d.f.

Mean

square

d.f.

Mean

square

Environmen

tstratum

Year

12.908***

20.6658**

21.497***

13.228***

20.5423

246.86***

Tim

eofsowing(TOS)

22.550***

21.057***

24.341***

26.908***

21.735**

21.491***

Year

´TOS

22.379***

30.2446

33.204***

23.555***

33.216***

31.818***

Residual

12

0.03267

16

0.09334

16

0.09399

12

0.01544

16

0.1657

16

0.03965

Accessionstratum,excludingem

ergence

ascovariate

Accession

24

0.05940***

24

0.05352***

24

0.04246

24

0.02003

24

0.05743*

24

0.3052***

Year

´accession

24

0.03160

48

0.05435***

48

0.05634***

24

0.02827

48

0.07774***

48

0.1396***

TOS

´accession

48

0.03687**

48

0.04992***

48

0.02300

48

0.04033*

48

0.04660

48

0.1416***

Year

´TOS

´accession

48

0.03162*

72

0.03679***

72

0.02982

48

0.04453**

72

0.03660

72

0.1807***

Residual

288

0.02065

382

0.01748

382

0.02764

288

0.02533

382

0.03639

376

0.02178

Accessionstratum,includingem

ergen

ceascovariate

Emergence

´year

´TOS

60.1289***

80.3600***

80.03456***

60.09642***

80.02166

80.1691***

Accession

24

0.06630***

24

0.05607***

24

0.04300**

24

0.02512

24

0.05975*

24

0.2864***

Year

´accession

24

0.02431

48

0.02451**

48

0.05401***

24

0.02941

48

0.08188***

48

0.1405***

TOS

´accession

48

0.03360**

48

0.04249***

48

0.01728

48

0.03735*

48

0.04520

48

0.1355***

Year

´TOS

´accession

48

0.03202*

72

0.03495***

72

0.02211

48

0.04434**

72

0.03663

72

0.1731***

Residual

282

0.01887

374

0.01513

374

0.02332

282

0.02383

374

0.03620

368

0.02196

*,**,***P<

0.05,0.01and0.001,respectively.

Temperature E�ects on Chickpea Growth 197

a pasture probe, generally provided poor correla-tions with dry matter production and no correla-tion was strong enough to be predictive andtherefore to be used instead of destructive drymatter determination. At 4 weeks, canopy widthand pasture-probe evaluation both had correla-tions with dry matter production of about 0.6,which was much better than plant height (Table 4).At 8 weeks, all three correlations were less than 0.5and at the onset of ¯owering, plant height andcanopy width were negatively correlated with drymatter production, an unexpected outcome, andthe pasture probe reading was very poorly corre-lated.Relative growth rates showed strong e�ects of

environment, but in the interval from 4 to 8 weeksafter emergence the main e�ect of accession wasnot signi®cant (Table 2). Outstandingly highgrowth rates from 4 to 8 weeks were achieved inthe second sowing of 1996 (Table 3). High growthrates from 8 weeks to ¯owering were achieved inthe late May sowing of 1994 and the June sowing of1995 (Table 3). The e�ect of emergence as acovariate was signi®cant between 4 and 8 weeks(Table 2) and was attributable to correlations of)0.0094 in the ®rst sowing of 1996 and ±0.0134 inthe third sowing of 1996 (0.0030 S.E.). Plantemergence was not a signi®cant covariate in thesecond interval. The accession term was relativelysmall in both intervals, whereas the environment ´accession terms accounted for much more of thevariance (Table 2). Outstandingly high relativegrowth rates between 8 weeks and the onset of¯owering were found in 8949-F6 and T2200, whilethe lowest relative growth rate was in Gully(Fig. 3).In 1995 and 1996, virus infection became a

problem soon after the onset of ¯owering and, inspite of insecticide treatments to kill the aphidvectors of the virus, most plants were killed orseverely stunted and yields were very low, about 0.2t ha±1 in 1995 and 0.6 t ha±1 in 1996 (Table 3). In1994, however, there were no apparent diseaseproblems and the yields were considered as repre-sentative. Because of the overwhelming e�ect ofdisease on the yields in the other two years, we donot report them here. In 1994, grain yield wasstrongly correlated with dry matter productionat the onset of ¯owering [yield� 1.25 (0.11 S.E.) +0.164 (0.039 S.E.) ´ dry matter; r� 0.517,P < 0.001] (Fig. 4). Desi line T1850 was thehighest yielding from both times of sowing andfour other lines, including one kabuli, all producedT

able

3:Environmen

tmeansofdry

matter,relativegrowth

ratesandgrain

yield

Dry

matter

production

Relativegrowth

rate

4weeksafter

emergence

8weeksafter

emergence

Onsetof

¯owering

4±8weeks

8weeksto

onset

of¯owering

Grain

yield

Environment

log

tha±1

log

tha±1

log

tha±1

log

gg±1

log

gg±1

log

tha±1

Late

May1994

)0.049

0.893

0.486

3.064

0.535

3.43

0.261

1.82

June1994

)0.101

0.792

0.004

1.010

0.106

1.28

0.130

1.35

EarlyMay1995

)0.417

0.383

0.014

1.033

0.414

2.594

0.431

2.70

0.400

2.51

)0.694

0.20

Late

May1995

)0.483

0.329

0.086

1.219

0.371

2.351

0.569

3.71

0.285

1.93

)0.629

0.23

June1995

)0.502

0.315

)0.010

0.976

0.508

3.221

0.492

3.10

0.518

3.30

)1.029

0.09

EarlyMay1996

)0.538

0.290

)0.069

0.854

0.308

2.033

0.470

2.95

0.377

2.38

)0.097

0.80

Late

May1996

)0.913

0.122

0.177

1.503

0.608

4.056

1.090

12.31

0.431

2.70

)0.238

0.58

June1996

)0.433

0.369

0.007

1.017

0.124

1.329

0.440

2.76

0.116

1.31

)0.103

0.79

S.E.

0.017

0.015

0.019

0.018

0.022

0.017

198 O'Toole et al.

over 2 t ha±1. Grain yield showed strong e�ects ofevery term in the analysis of variance (Table 2).Although emergence was a signi®cant covariate inthe analysis, none of the individual slopes wassigni®cantly di�erent from zero and the signi®cancewas attributable to the di�erence between theminimum slope, for the June 1994 sowing, andthe maximum, for the June 1995 sowing.

Controlled-environment experiment

Germination and seedling phaseGermination was signi®cantly a�ected by tempera-ture, but not by accession. At 13/8 °C, only 68 %of seeds germinated, but at 18/8 °C and 23/13 °C,90 % germinated.

The temperature and accession terms and theirinteraction were signi®cant for dry matter produc-tion (Table 5). The e�ect of age was also signi®cantand so was the age by temperature interaction, butnone of the other interactions with age wassigni®cant. The greatest dry matter production at10 days was in the 23/13 °C regime, but at 30 daysit was in the 18/8 °C regime (Table 6). At 20 daysthe weights in these two environment were notsigni®cantly di�erent. The coldest environmentalways yielded the lowest dry matters.The accession±temperature interaction was due

to some lines performing more poorly at 23/13 °Cthan at 18/8 °C while others performed better(Fig. 5). Kabuli lines Garnet and SP1.563 hadgenerally the highest dry matters, regardless of age

Fig. 1: Dry matter produc-tion of 25 chickpea acces-sions at the onset of¯owering in time-of-sowingexperiments. Environmentsare in order of mean yieldrather than chronologicalorder

Fig. 2: Dry matter produc-tion of 25 chickpea acces-sions, as percentage ofaverage across times ofsowing, at 4 weeks afteremergence (black histo-gram, left-hand error bar),8 weeks after emergence(hatched histogram, middleerror bar) and the onset of¯owering (grey histogram,right-hand error bar). Errorbars show � 1 standarderror

Temperature E�ects on Chickpea Growth 199

and temperature. Amethyst, Barwon, Desavic,8803-7H, Gully and Lasseter had optimum drymatters at 18/8 °C rather than at 23/13 °C at both20 and 30 days. The di�erence between these twoenvironments was particularly large in cultivarGully. L550, Garnet and SP1.563 all had signi®-cantly higher dry matter yields at 23/13 °C than at18/8 °C at both 20 and 30 days, while in line 8950-18F6 there was little di�erence. This consistency inperformance at 20 and 30 days accounts for thelack of signi®cance of the age ´ temperature ´interaction term in the analysis of variance.The growth rate was signi®cantly a�ected by

temperature but not by accession (Table 5). Thedry matter yield of plants was multiplied 5-fold inthe second 10 days of growth in the two coolertemperature regimes but only 2-fold in the warmestenvironment (Table 6). In the third 10 days of

Table 4: Phenotypic correlations

Emergence Dry matter Plant height Canopy width

4 weeks after emergenceDry matter 0.055 bPlant height )0.074 c 0.238 cCanopy width )0.130 e 0.593 e 0.613 ePasture probe 0.336 d 0.617 d 0.123 e 0.110 g

8 weeks after emergenceDry matter 0.294 aPlant height 0.315 c 0.479 cCanopy width 0.619 c 0.338 c 0.467 cPasture probe 0.330 d 0.454 d 0.784 e )0.245 e

At onset of ¯oweringDry matter 0.241 aPlant height 0.326 c )0.373 cCanopy width )0.105 f )0.760 f 0.804 fPasture probe )0.201 g 0.213 g )0.100 g h

a, 200 observations; b, 150; c, 125; d, 100; e, 75; f, 50; g, 25; h, 0.

Fig. 3: Relative growthrates of 27 chickpea acces-sions (g g±1 interval±1). Forthe ®eld experiment (greyhistograms, left error bar),the interval was from week8 to the onset of ¯oweringin ®eld experiments. For thecontrolled-environment ex-periment (black histograms,right error bar), the intervalwas 20 days and data showthe average growth rate fordays 30±50 and days 50±70.Error bars show � 1 stand-ard error

Fig. 4: Grain yield and dry matter at the onset of¯owering in 25 chickpea accessions at two times ofsowing in 1994 ®eld trials: h, late May sowing; d, Junesowing. Error bars show � 1 standard error

200 O'Toole et al.

growth, the rate of dry matter accumulationcontinued to be greatest in the coolest environment.This di�erence illustrates the signi®cance of the age´ temperature term in the pooled analysis ofvariance (Table 5).Genotypic correlations of other factors with

germination were not relevant, as genotypic vari-ation in germination was not signi®cant. Pheno-typic correlations of other factors with germinationwere attributable to the major e�ect of tempera-ture. Genotypic correlations of dry matter produc-tion at di�erent ages were very high, above 0.97(Table 7). The phenotypic correlation between drymatters at 20 and 30 days was comparably high,but dry matter at 10 days was more weaklycorrelated with subsequent values owing to thelarge e�ect of temperature. Growth rates in the twointervals were weakly correlated. The genotypic

correlations of growth rates with dry matter yieldswere positive whereas the corresponding pheno-typic correlations were negative, because of theoverriding e�ect of temperature. Genotypic corre-lations of growth rate from 20 to 30 days with drymatter data were much lower than those of thegrowth rate from 10 to 20 days, whereas pheno-typic correlations were generally stronger becauseof the strong e�ect of temperature on growth rate.

Vegetative phaseThe dry matter yields of the vegetative plants didnot di�er signi®cantly between environmentsbefore introduction to the growth chambers, con-®rming that the sample was unbiased at the start ofthe experiment. Dry matter production was signi-®cantly a�ected by temperature, accession, age,age ´ temperature and age ´ accession, but the

Table 5: Summary analysis of variance, using the repeated-measures model, of dry matter production (logtransformed) and relative growth rate in chickpea grown in three temperature regimes. In the seedling phaseexperiment, 10 accessions were evaluated at 10, 20 and 30 days after planting and in the vegetative phase, 25accessions were evaluated at 30, 50 and 70 days after planting

Seedling phase (0±30 days) Vegetative phase (30±70 days)

Dry matter Growth rate Dry matter Growth rate

Source of variation d.f. Mean square d.f. Mean square d.f. Mean square d.f. Mean square

Temperature 2 30.25*** 2 185.7*** 2 0.2710*** 2 1.776Accession 9 0.9876*** 9 4.065 23 0.1969*** 23 10.05***Temperature ´ accession 18 0.09051*** 18 2.188 46 0.02326 46 2.600Residual 150 0.03059 150 2.180 139 0.02277 139 3.800Age 2 44.49*** 1 84.14*** 2 62.14*** 1 77.03***Age ´ temperature 4 1.832*** 2 88.70*** 4 0.2828*** 2 133.3***Age ´ accession 18 0.01942 9 3.677 46 0.05584*** 23 7.923Age ´ temperature

´ accession36 0.01603 18 1.332 92 0.02184 46 8.170

Residual 290 0.01394 145 2.595 278 0.02599 139 6.383Epsilon factor for

d.f. adjustment0.81 1.00 0.93 1.00

***P < 0.001.

Table 6: Mean dry matter yields (log transformed and back-transformed means) at 10, 20 and 30 days afterplanting and relative growth rate from 10 to 20 days and from 20 to 30 days, for 10 chickpea accessions grown inthree temperature regimes

Temperature

Dry matterat 10 days

Dry matterat 20 days

Dry matterat 30 days

Relative growth rate[g g±1 (10 days)±1]

(°C) log g log g log g 10±20 days 20±30 days

13/5 )1.329 0.047 )0.666 0.216 )0.027 0.940 5.01 4.4618/8 )0.603 0.250 0.093 1.238 0.486 3.063 5.46 2.5523/13 )0.215 0.609 0.055 1.136 0.419 2.622 2.00 2.52S.E. 0.024 0.012 0.015 0.25 0.12

Temperature E�ects on Chickpea Growth 201

temperature ´ accession and age ´ temperature ´accession terms were not signi®cant (Table 5). Thetemperature ´ age term was due to there being no

signi®cant di�erence between dry matter yieldsamong the temperatures at 30 days or again at 70days, but all di�erences being signi®cant at 50 days,with the greatest dry matter accumulation at theintermediate temperature (Table 8). The highestyielding line di�ered at each age, being Bumper atthe start, 940-26 at 50 days and Dooen at the endof the experiment (Fig. 6). The highest average drymatter production was in Bumper, followed bySP1.563 and 940-26.Growth rate was signi®cantly a�ected by the

age ´ temperature interaction, age and accession,although the main e�ect for temperature was notsigni®cant and none of the interactions withaccession were signi®cant (Table 5). During the®rst interval, dry matter yields were multipliedabout 5-fold in the two warmer environments andonly 3.5-fold in the cooler one, but during thesecond interval the most rapid growth was in thecoolest environment (Fig. 3). The highest growthrate was found in the desi accession T1850, whichincreased in dry matter 6 times in each 20-dayinterval, and the lowest in kabuli cultivar Bumper,which increased in dry matter less than 3-fold ineach interval. Nevertheless, T1850 remained low indry matter production at the end of the experimentand Bumper was intermediate.

Table 7: Phenotypic (below diagonal, d.f. = 28) and genotypic (above diagonal, d.f. = 8) correlation coe�cientsfor seedling plant data from 10 chickpea accessions grown in three temperature regimes

Dry matter Growth rate

10 days 20 days 30 days 10±20 days 20±30 days

Dry matter 10 days Ð 0.975** 0.980** 0.821**20 days 0.794** Ð 0.991** 0.908**30 days 0.764** 0.980** Ð 0.862**

Growth rate 10±20 days )0.626** Ð20±30 days )0.606** )0.704** )0.595** 0.371* Ð

*P < 0.05; **P < 0.01.

Table 8: Mean dry matters at 0, 20 and 40 days after moving to controlled-environment chambers (aged 30 days)and relative growth rates of 24 chickpea accessions grown in three temperature regimes

Dry matterRelative growth rate

30 days 50 days 70 days [g g±1 (10 days)±1]

Treatment log g log g log g 30±50 days 50±70 days

Temperature13/5 °C )0.724 0.189 )0.228 0.592 0.396 2.49 3.52 4.8618/8 °C )0.688 0.205 )0.024 0.947 0.364 2.31 5.16 2.7623/12 °C )0.724 0.189 )0.084 0.824 0.372 2.36 4.97 3.38S.E. 0.019 0.019 0.019 0.27

Fig. 5: Dry matter at 30 days after sowing for 10chickpea accessions (j, Amethyst; d, Barwon; m,Desavic; r, Garnet; h, L550; s, SP1.563; n, Gully;e, Lasseter; ., 8803-7H; ,, 8950-18F6) in threeenvironments. Error bars show � 1 standard error

202 O'Toole et al.

Dry matter production at 50 days was signi®-cantly correlated with dry matter production at thestart, but this e�ect was lost by 70 days (Table 9).Dry matter values and the relative growth rates inthe subsequent interval showed strong negativecorrelation coe�cients, with the phenotypic corre-lation showing the strong additional e�ect oftemperature. Thus, the lower the initial dry matter,the greater the subsequent growth rate. The corre-lation of dry matter production with the growthrate in the preceding interval was smaller andpositive, and non-signi®cant in the genotypic case.

Discussion

Seedling emergence

Seedling emergence in the ®eld often failed to reachthe targeted value of 40 plants m±2 in spite of pre-sowing germination tests. The controlled-environ-ment studies showed that low temperatures couldaccount for part of this poor emergence. Never-theless, there was no consistent trend with time ofsowing, so it is unlikely that failure to reach thisemergence value can be attributed entirely totemperature. Siddique and Sedgley (1986), in quite

a di�erent environment, reached a similar conclu-sion. This suggests that chickpeas are already betteradapted to being sown in warm autumn soils thanin cool spring soils. OÈ zdemir (1996) found progres-sively better chickpea germination in warmer soilsat 10 , 15 and 20 °C and that cultivars behavedsimilarly. Ellis et al. (1986), however, found thatchickpea accessions varied in sensitivity to tem-perature at germination, with some requiring afairly narrow range of 10 to 20 °C and others beinguna�ected between 2 and 40 °C. Temperatures of13 °C, commonly found in spring planting, sup-pressed chickpea germination (Auld et al. 1988).The 18/8 °C regime provided an average tempera-ture of 13 °C, yet allowed slightly greater ®nalpercentage germination than the warmer regime.Thus it may be inferred from the present results,where diurnally varying temperatures were used,that it is the warmer temperature that is mostimportant in germination.The positive correlation between seedling emer-

gence, when it was poor and variable, and drymatter production m±2 as late as the onset of¯owering con®rms that the establishment of anadequate plant stand is essential for optimum crop

Table 9: Phenotypic (below diagonal, d.f. = 70) and genotypic (above diagonal, d.f. = 22) correlation coe�cientsfor vegetative phase data from 24 chickpea accessions grown in three temperature regimes

Dry matter Growth rate

30 days 50 days 70 days 30±50 days 50±70 days

Dry matter 30 days Ð 0.514** )0.656** )0.596**50 days 0.369** Ð 0.611** )0.578**70 days Ð

Growth rate 30±50 days )0.502** 0.494** Ð50±70 days )0.301* )0.756** 0.451** )0.395** Ð

*P < 0.05; ** P < 0.01.

Fig. 6: Dry matter produc-tion of 24 chickpea acces-sions, as percentage ofaverage across tempera-tures, at 30 days after sow-ing (black histogram), 50days (hatched histogram)and 70 days (grey histo-gram). The error barshows � 1 standard error

Temperature E�ects on Chickpea Growth 203

yield in this species (Singh et al. 1988, Kasole et al.1995) and suggests that its ability to compensatefor poor establishment is limited.In the controlled environments, ®nal percentage

germination was consistent across the genotypestested. Field emergence, however, was particularlypoor in kabuli types. Kabuli chickpea testasgenerally have much lower pigmentation thanthose of desi types and pigmented seed coats havebeen associated with reduced cold imbibition injuryin peas (Powell 1989) and improved germination offaba beans in cold soils (Kantar et al. 1994). Kabulitestas are also relatively thin (Kumar and Singh1989, Gil and Cubero 1993) and this has beenidenti®ed as responsible for their greater suscepti-bility to damage during harvest (Auld et al. 1988).Such damage would also contribute to poor ®eldemergence. Seed coat thickness in a desi ´ kabulicross was attributed to several genes with partialdominance for thicker coats and no signi®cantassociation with seed size (Kumar and Singh 1989).Thus it should be possible to achieve a balancebetween the needs for thicker kabuli seed coats tomaintain viability and thinner desi seed coats tomaximize yield of dehulled cotyledons for humanconsumption.

Optimum time of sowing

Dry matter production was generally greatest fromthe middle (late May) sowing. This generalizationheld true for dry matter at 8 weeks in all three yearsand at the onset of ¯owering in two years and alsofor yield in two years. In this environment, a lateMay sowing appears to o�er the best compromisebetween early sowing into warm soil and latesowing to avoid frost at ¯owering. This optimumtime, of a few weeks before the winter solstice,corresponds to that found elsewhere in Australia(Pye 1980, Siddique and Sedgley 1986, Horn et al.1996), Sudan (Ageeb and Ayoub 1976), Syria(Hughes et al. 1987) and India (Lal et al. 1980,Dixit 1992). This timing optimizes solar energy useand water use (Hughes et al. 1987, Dalal et al.1997) while minimizing opportunities for frostdamage to intolerant plant parts such as pollen(Srinivasan et al. 1999).Indirect measures of dry matter production,

including plant height, canopy spread and pas-ture-probe conductivity, were all relatively poor aspredictors when evaluated at a uniform plant age,although the correlations were often signi®cant. Itappears, then, that there is no substitute for direct

measurement of dry matter production. Dry matterproduction, in turn, was signi®cantly correlatedwith ®nal grain yield in the one year when yielddata were valid, in agreement with previous reports(Singh et al. 1990, Omar and Singh 1997).In these experiments, it was not possible to

obtain a valid measure of ®nal crop yield in two ofthe three years, because of the severe e�ect ofviruses on the plants. Aphids arrived soon after theonset of ¯owering in 1995 and 1996, carryingviruses, and the plants were severely stunted orkilled as a result. The viruses were subsequentlyidenti®ed as bean leafroll luteovirus and subterra-nean clover redleaf luteovirus (Schwinghamer et al.1999). Dry matter evaluation up to the time of¯owering was not a�ected by this and so may beviewed as reliable. Virus or aphid resistance is animportant breeding objective for chickpeas in thisenvironment.

Identifying sources of better dry matter production

Vigorous production of dry matter, much of whichoccurs during the vegetative phase, is widely viewedas essential for high grain yields in grain legumes(Leport et al. 1998, Siddique et al. 1998, Siddiqueet al. 1999) as in other crops. A strong vegetativephase provides an adequate framework to hold thecrop and a suitable basis for partitioning into grainyield. An important further justi®cation behind theshift to winter sowing of chickpeas and lentils hasbeen the avoidance of stress due to low rainfall andhigh temperatures during spring and summer (vanRheenen et al. 1991, Singh et al. 1993, Siddiqueet al. 1998). Thus dry matter production in lowtemperatures during the vegetative phase hasbecome of greater importance. In the ®eld-basedtime of sowing experiments, air temperature, soiltemperature, day length, water availability, solarirradiation and other environmental componentswere all confounded and it was di�cult to resolvewhich was the most important in¯uence on drymatter production. The controlled-environmentgrowth chambers, in contrast, tested the e�ects oftemperature alone.Genotype ´ environment e�ects were very large

in the ®eld experiments and generally accounted fora greater proportion of the variance than thegenotype main e�ect, as is common in chickpeatrials (Kumar et al. 1996). Nevertheless, severalaccessions were consistently in the top 20 % oflines evaluated and other accessions were outstand-ing in only one growth interval.

204 O'Toole et al.

In the seedling phase, up to 30 days after emer-gence, the controlled-environment experiment iden-ti®ed accessions SP1.563 and Garnet as beingcontinuously outstanding in dry matter productionat all temperatures. This result was partly con®rmedat the start of the vegetative-phase experiment,where Bumper (not used in the seedling experiment)and SP1.563 had the two highest values of drymatter production. These lines were surpassed byseveral others in the corresponding interval in the®eld experiment, where Barwon and Dooen werethe highest in drymatter across environments. In thenext 4 weeks in the ®eld trial, two other lines, 940-26and Mission, passed these, while in the next 20 daysin the controlled environments, 940-26 and Garnethad the highest dry matter production. In theremaining interval, up to the onset of ¯owering, line8838-4H was outstanding in the ®eld and Dooen inthe controlled environments.Breadth of adaptation was also shown by some

accessions. The consistently high performance ofSP1.563 and Garnet in the seedling experiment inthe growth cabinets was in strong contrast to thevery narrow adaptation shown by cultivar Gully.Wide adaptation is a breeding target in somechickpea programmes (Auckland and Singh 1977,Silim and Saxena 1993) as in faba bean (Link et al.1996) and wheat (Braun et al. 1996) as regional-speci®c adaptation is viewed as providing risks ofbroad maladaptation.Relative growth rate in the seedling phase was

found to depend strongly on temperature, and alsoon time, but not on genotype. This suggests thatthe optimum strategy for dry matter accumulationis to use genotypes that establish early as largeseedlings, as the environment is the primary deter-minant of growth rate and the ability of weakaccessions to catch up with vigorous ones islimited, at least in the evaluated germplasm. Inthis experiment, early rapid growth was found inthe large-seeded kabuli types, as also noted by Auldet al. (1988). The correlation between embryo sizeand seedling vigour or establishment is well knownin many species, including faba bean (Nachi and LeGuen 1996) and common bean (Ries 1971). Infor-mation on this correlation in chickpea is contra-dictory (e.g. positive correlation, Roy et al. 1994;negative correlation, Raje and Khare 1996). Theimportance of seedling-phase dry matter accumu-lation for grain yield is often high (e.g. in fababean, Mwanamwenge et al. 1998) but depends agreat deal on subsequent growing conditions(TeKrony and Egli 1991).

Although the large-seeded kabuli types showedthe best seedling growth, it was the smaller-seededdesi types that had the greatest relative growthrates in the vegetative phase. The result was thatthe greatest dry matter production at the end of theexperiment was in desi types. This trend, however,was not universal among the desi types, as thelowest dry matter production was also foundamong them. Crosses between the two chickpeatypes often show very high heterosis (Rao andChopra 1989) and may lead to useful recombina-tion of the strong seedling growth of kabulis withthe high relative growth rate of the desis.It is clear that some of these accessions are better

suited to early dry matter production and others tolater dry matter production. It should be possibleto recombine these traits into continuously out-standing dry matter production in a targetedbreeding programme. In these accessions, coldtolerance seemed to be more a part of generalvigour than a separate factor, as shown by thestrong performance of `cold-tolerant' material atnon-chilling temperatures.

Acknowledgements

This research was funded by the Grains Research andDevelopment Corporation of Australia and representedpart of the PhD thesis of N.O'T. accepted by the Universityof Sydney.

Zusammenfassung

Selektion von Kichererbse auf EignungfuÈ r Herbstaussaat

Die Trockenmasseproduktion wurde an 27 Kichererbsen-linien in AbhaÈ ngigkeit von dem Aussaattermin in Feldun-tersuchungen und in Wachstumskammern bei 13 °CTages-/5 °C Nachtemperatur sowie 23/13 °C hinsichtlichder Toleranz gegenuÈ ber wachtumsinhibierenden Tempera-turen untersucht. Die Felduntersuchungen wurde inNarrabri, NSW, Australien, in einer Region mitSommerniederschlaÈ gen, bei denen Winteranbau auf Feu-chtigkeitsbevorratung beruht, durchgefuÈ hrt. Die Au¯auf-prozente waren in den Feldversuchen und den kuÈ hlerenKammerversuchen geringer als erwartet. Als Folge zeigtedie Trockenmassebildung bis zum Beginn der BluÈ te denEin¯uû des schwachen Au¯aufens der Saaten. Kabuli-Typen waren emp®ndlicher als desi-Typen gegenuÈ ber demschwachen Au¯auf. Unterschiedliche Linien gaben diehoÈ chsten ErtaÈ ge zu unterschiedlichen Wachstumsstadien.Im SaÈ mlingstadium, 30 Tage nach Au¯aufen, zeigten diekabuli.Linien SP1.563 und Garnet unter kontrolliertenWachtumsbedingungen eine signikant groÈ ûere Troc-kenmasseproduktion im Vergleich zu allen anderen

Temperature E�ects on Chickpea Growth 205

Linien, was auf ein breites Spektrum der Adaption hin-weist. Eine desi-Linie, Gully war annaÈ hernd so produktivwie diese beiden Linien; sie war allerdings viel schwaÈ cherunter den anderen Umweltbedingungen, was auf eine engeAdaption schlieûen laÈ ût. In der vegetativen Phase wurdendie hoÈ chsten relativen Wachstumsraten in den desi-Liniengefunden. Linie 940-26 wurde als hoch produktiv unter dendesi-Linien unter Feld- und kontrollierten Wachstumsbe-dingungen nachgewiesen. Die Trockenmasseproduktionwar nicht signi®kant von der Temperatur abhaÈ ngig,obwohl sie leicht erhoÈ ht war in der kuÈ hlsten Behandlung.Die Linien zu Temperatur Interaktion war nicht signi®k-ant; danach ist die Breite der Adaption in allen Linienwahrend des Wachstums vergleichbar. Der optimale Sa-atzeitpunkt fuÈ r die Trockenmasseproduktion war der spaÈ teMaÈ rz, 4±6 Wochen vor der Wintersonnenwende. DieErgebnisse zeigen, daû Kichererbsen gut in der Keimungund im SaÈ mlingswachstum fuÈ r gemaÈ ûigte Klimabedingenadaptiert sind; das vegetative Wachstum ist auch unterkuÈ hleren Bedingungen gut. Diese Voraussetzungen sindtypisch fuÈ r eine Herbstaussat in einem mediterranen Klima.Kabuli-Typen scheinen ein staÈ rkeres Wachstum waÈ hrendder SaÈ mlingsphase und desi-Typen waÈ hrend der vegetativenPhase zu haben. Rekombination dieser EigenschaftenkoÈ nnte zu produktiveren Kultivaren fuÈ hren.

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