J. Agronomy & Crop Science, 156, 133—137 (1986)© 1986 Paul Parey Scientific Publishers, Berlin and HamburgISSN 0044-2151

Indian Grassland and Fodder Research Institute, Jhansi (India)

Studies on some Drought Resistant Traitsof Pearl Millet Cultivars and their Association

with Grain Production under Natural Drought

MASOOD ALI, B . D . PATIL, N . C . SINHA and C. R. RAWAT

Authors' addresses: Dr. MASOOD ALI, Principal Investigator (Agronomy) Directorate of PulsesResearch, Kanpur 208 024 (India), Dr. B. D. PATIL, Director, Dr. N. C. SINHA, S-2 (PlantPhysiology), and Dr. C. R. RAWAT, S-2 (Agronomy), Indian Grassland and Fodder Research

Institute, Jhansi-284003 (U.P.), India.

With 3 tables

Received June 3, 1985; accepted August 19, 1985

Abstract

A field experiment was conducted to evaluate the performance of hybrid (BJ 104, MBH 110,CM 46 and GHB 27) and composites (PSB 3, PSB 8, WCC 75 and Local) of pearl-millet on thesoils (pH 7.1, Organic carbon 0.5 %, P7O5 9.6 kg/ha, K2O 80 kg/ha, soil depth 65 cm andprofile moisture 8.6 cm) of Indian Grassland and Fodder Research Institute, Jhansi underextreme drought condition (340 mm total precipitation during the crop season). It was observedthat hybrids, by and large, gave higher production than composites and local variety even failedto bloom. Further the highest yield from hybrid MBH 110 was due to its drought escapingcharacter (earliness), drought enduring capacity (CSI-12), efficient translocation and better sinkstrength. BJ 104 and CM 46, though were also drought escaping and possessed capacity toendure drought but inferior to MBH 110 in sink strength which was ultimately reflected inproduction.

An appraisal of the various agro-physiological traits revealed that earliness, high harvestindex, low CSI value (chlorophyll stability index) and high sink strength were directlycorrelated with productivity of cultivars under drought condition which could be used as aguide lines for breeding drought resistant cultivars of pearl millet.

Key Words: Pearl Millet, Drought resistant traits. Chlorophyll stability index. Chlorophyllcontent. Harvest index.

I. Introduction

Pearl millet (pennisetum americanum (L.) Leake) is an important crop of arid and semi-arid tropics. In India, it is cultivated on 14 million hectares. Of this, 96 per cent are rainfedand' susceptible to various degree of natural hazards, particularly drought. Under thesecondition, identification of drought resistant and high yielding cultivars would be a keyfactor for stabilization and enhancing pearl millet production.

In past, the identification of drought resistant crops and varieties has been done byassessing their performance under various degree of soil moisture stress (soil drought).

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134 ALI, PATIL, SINI-IA and RAWAT

Such observation do not reflect true reaction of cultivars to natural drought which includeatmospheric and soil drought together on the resultant crop performance.

A correlation studies between various agro-physiological traits and grain productionmade under natural drought condition would provide a realistic approach to screencultivars having drought resistant capacity (MAY and MILTHROPE 1962). The presentinvestigation was, therefore, undertaken under natural drought condition to find out highyielding and drought resistant cultivars of pearl millet for semi-arid regions of India andwork out the relationship between agro-parameters and grain production.

II. Materials and Methods

Field studies were made on 8 cultivars i.e. four hybrids (BJ 104, MBH 110, CM 46 and GHB27) and four composite (PSB 3, PSB 8, WCC 75 and local) of pearl millet at Indian Grasslandand Fodder Research Institute, Jhansi during monsoon (July-Sept.) 1979. The soil of experi-mental site was loamy sand with pH 7.1, organic carbon 0.5 %, available phosphorus 9 kg/haand available potash 80 kg/ha. The depth of the soil and profile moisture at field capacity was65 cm and 8.6 cm, respectively.

The experiment was carried out in randomized block design with three replications. Seedingof all cultivars was done on 29th June in rows spaced at 50 cm. An uniform placement of 60 kgN + 30 kg P2O5 per hectare was done. After 15 days of planting, plant to plant distance wasmaintained at 15 cm. Five plants were selected randomly for recording various agro-physiologi-cal observations. For determination of chlorophyll content and chlorophyll stability index(CSI), the third leaf from the top was taken when incipient wilting occurred after 15—20 days ofdrought. Chlorophyll content and chlorophyll stability index were determined by the methodsof DUXBURY and YENTESCH (1956) and MuRri' and MAZUMDAR (1962) respectively. The cropseason was characterized by acute drought. The total precipitation during crop season was340 mm only and the distribution was highly erratic. The number of rainy days were 19.

III. Results and Discussion

All the hybrids excepting GHB 27, gave significantly higher yield than composites(Table 1). Hybrid MBH 110 was found to be the highest yielding (1270 kg/ha) followed byBJ 104 (1000 kg/ha) and CM 46 (879 kg/ha) under acute drought condition. Amongstcomposites, PSB 8 gave highest yield (513.0 kg/ha) though it was at par with PSB 3. Thelocal variety could not even flower due to severity of drought. It was observed that MBH110 took minimum number of days to mature (69 days). The lowest yielding cultivar(WCC 75) took maximum number of days to mature (80 days). This obviously reveals aclose relationship between duration and productivity. These varieties which maturedearlier escaped the adverse effect of drought to some extent. Similar treatments were alsogiven by MAY and MILTHROPE (1962). They stated that success in adapting by shortening ofgrowth cycle of crops so that the plant matures before soil water limit yield. However,given adequate water supply, yield is usually positively correlated with maturity date, sothat in practice under drought condition a grower has to off set the potentially highyielding late maturing variety on account of the risk of yield reduction due to early stress.Similar findings have been reported by BAGGA et al. (1973). Further it was observed thathigh yielding cultivars had high harvest index indicating thereby better translocationefficiency. FRIEND (1966) also observed that a large ratio of grain to total dry weight is acharacteristics of new high yielding varieties, but it may be the results of concious selectionof short stiff rather than for large yield of grain with minimum production of total drymatter.

Studies on some Drought Resistant Traits of Pearl Millet Cultivars

Table 1 Agro-morphological characters of pearl millet

135

Cultivars

MBH 110BJ 104CM 46GHB27PSB3PSB8WCC 75LocalLSD (0.05 p)

No. ofbasal

tillers/plant

5.25.17.06.36.65.24.76.01.2

No. ofgrains

bearingtillers/plant

2.43.54.93.73.42.91.90.01.1

Lengthof ear(cm)

26.924.322.323.930.829.025.4

0.05.2

Girthof ear(cm)

8.05.45.15.66.85.96.20.01.6

Grainyield

(kg/ha)

127010008793554715131500.02.0

Dura-tion

(days)

67717180767680——

An appraisal of the yield contributing parameters reveal that basal tillers were highest inCM 46 which was closely followed by PSB 3, GHB 27 and local, though all werestatistically on par. The effective tillers were, however, significantly more in CM 46 thanPSB 3 and GHB 27 and local, though all were statistically on par. The effective tillers were,however, significantly more in CM 46 than PSB 3 and GHB 27 which indicates betterutilization of photosynthetes towards the build up of higher sink. Among hybrids, MBH110 and BJ 104 had fewer basal and fertile tillers than CM 46 but higher sink strength (asreflected by girth of ear with fertile grains) in the former one led to more efficienttranslocation and consequently more filled grains. It can be speculated from the abovefindings that under drought conditions, plants producing fewer tillers with maximum sinkstrength will synthesize enough synthates which may be utilized to their full capacityduring the reproductive phase as compared to those bearing maximum basal tillers.Because the plants which bear higher basal tillers lost their assimilated synthates inunproductive tiller formation and remaining assimilates seems to be insufficient in produc-ing maximum filled grains. The ear length was highest in PSB 3 though it was at par withMBH 110, PSB 8 and WCC 75. Pigmentation was more in PSB 3 (5.389 mg/l/g freshweight), GHB 27 and BJ 104 whereas WCC 75 had lowest value (4.048 mg/l/g freshweight). The chlorophyll-a, on the other hand, was lower in PSB 3, MBH 110 and CM 46and higher in GHB 27. Chlorophyll stability index (index of drought resistance) waslowest for PSB 3 (CSI-2) followed by CM 46, MBH 110 and BJ 104 (CSI-13). Lower thevalue of CSI represents the highest drought resistance capacity (MURTI' and MAZUMDAR

1962). Thus PSB 3 showed highest degree of drought resistant capacity and chlorophyllpigmentation but did not produce higher yield under drought condition possibly due tolow sink strength (Table 2). It is contemplated that this cultivar utilized much photosyn-thates for ear formation and consequently could not produce larger number of filled grainsdue to limited food reserves at later stages.

The correlation studies (Table 3) revealed that duration, harvest index, chlorophyllstability index, girth of ear and chlorophyll b had good relationship with grain production(Table 3) and consequently drought resistant capacity. The correlation with harvest index(r = -1-0.49) and girdth of ear (r = -1-0.58) was positive whereas with duration (r = —0.82),chlorophyll stabiHty index (r = —0.66) chlorophyll b (r = —0.57), it was negative.

136 ALI, PATIL and RAWAT

Table 2 Physiological characters of peral millet

Cultivars

MBH 110BJ 104CM 46GHB27PSB 8PSB 3WCC75Local

Harvestindex

17.614.913.04.5

10.56.12.50.0

Chlorophyllstabihty index

12.013.08.0

10.517.02.0

36.027.0

Chloro-phyll-a

2.1632.6852.5802.6022.1493.8311.0951.517

Chlorophyll mg/l/gfresh weight

Chloro-phyll-b

2.0332.7052.0393.2232.3662.0112.9022.783

Totalchlorophyll

2.2425.3425.1625.7874.5615.8894.0484.351

Table 3 Correlation coefficient (± r) between grain yield vs agro-physiological traits

TraitsValue of

correlationcoefficient (± r)

TraitsValue of

correlationcoefficient (± r)

Basal tillersEffective tillersEar lengthEar girthDuration

t ± (0.5) = 0.71

— 0.050.630.470.58

— 0.82=--

Harvest indexChlorophyll-aChlorophyll-bTotal chlorophyllC.S.L

— 0.98-0.35

— 0.570.10

— 0.65

From these it was observed that highest grain yield from hybrid MBH 110 was due to itsdrought escaping character (early maturity), drought enduring capacity (CSI-12), efficienttranslocation and better sink strength. BJ 104 and CM 46, though were also droughtescaping and possessed capacity to endure drought but were inferior to MBH 110 in sinkstrength which was ultimately reflected in production.

It may be concluded that under drought conditions, earliness, high harvest indexcoupled with high sink strength and low CSI which had fairly good positive correlationwith grain yield may be considered for breeding purposes. With appropriate modifica-tions, some of these characters particularly CSI may be of economic value for fodderimprovement of pearl millet also investigations on these lines are in progress.

Zusammenfassung

Untersuchungen an einigen Eigenschaften der Trockenheitsresistenzvon Perlhirse-Sorten und ihre Beziehungen zur Kornproduktion

unter naturlichen Trockenheitsbedingungen

Es wurde ein Feldexperiment durchgefiihrt, um das Verhalten von Perlhirse-Hybriden(BJ 104, MBH 110, CM 46 und GHB 27) und zusammengesetzten Sorten (PSB 3, PSB 8,WCC 75 and Local) auf Boden (pH 7,1, organischer Kohlenstoff 0,5 %, 9,6 kg PjOj/ha,80 kg K2O/ha, Bodenprofiltiefe 65 cm, Feuchtigkeit 8,6 cm) am Indian Grassland and

Studies on some Drought Resistant Traits of Pearl Millet Cultivars 137

Fodder Research Institut, Jhansi, unter extremen Trockenheitsbedingungen (340 mmTotalniederschlag wahrend des Anbaus) zu untersuchen. Es wurde beobachtet, dafi dieHybriden im grofien und ganzen eine hohere Produktion aufwiesen als die zusammenge-setzten Sorten und die lokale Sorte, die nicht einmal zur Bliite kam. Weiterhin zeigte sich,dafi der hochste Ertrag von der Hybride MBH 110 eine Fole der Friihzeitigkeit dieser Sortewar, wahrend die Trockenheitsresistenz und eine effiziente Translokation und besseresink-Starke fiir die Sorte CSI-12 festgestellt wurden. BJ 104 und CM 46, die ebenfallsTrockenheit aufgrund ihrer Friihzeitigkeit ertrugen, waren der Sorte MBH 110 in der sink-Starke, die letztlich die Produktion widerspiegelt, unterlegen.

Von den verschiedenen agro-physiologischen Eigenschaften erwies sich die Friihreife,ein hoher Ernteindex, geringer CSI-Wert (Chlorophyllstabilitatsindex) und hohe sink-Starke unmittelbar korreliert mit der Produktivitat der Sorten unter Trockenheitsbedin-gungen; diese Eigenschaften konnen als Orientierungslinien fiir die Ziichtung auf Trocken-heitsresistenz bei Perlhirse betrachtet werden.

References

BAGGA, A. K., M. M. GHARE, and R. D. ASANA, 1972: Physiological analysis of response ofsorghum hybrids 'CSH 1' and *CSH T to rainfed cultivation. Indian J. Agric. Sci. 43,225—228.

DUXBURY, A. C , and C. B. YENTESCH, 1956: Plankton pigment monograph. J. Marine Res. 15,92—101.

FRIEND, D . J. C , 1966: The growth of cereal and grasses. 181—199 Ed. MILTHROPE, F . D . andJ. D. IviNS, London Butterworth.

MAY, L. H . , and F. L. MILTHROPE, 1962: Field Crop Abstract 15 (3), 1—9.HARD, E. A., 1971: Drought injury and Resistance in crops Pub. No. 2 crop Sci. Sec. America,

Madison, Wisconsin 53711, 77—78.MuRTY, K. S., and S. K. MAZUMDAR, 1962: Modification of the technique for the determination

of chlorophyll stability index in relation to studies of drought tolerance in rice. Curr. Sci.31, 470—471.

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