pigeonpea hybrids lecture pp zaveri

Pigeonpea Hybrids – Present Status, Problems, Prospects and Quality Seed Production

by

Dr. P. P. ZaveriCEO & Proprietor

Biogene Agritech, Ahmedabad

Presented during Agricultural Research Council Meet at Anand Agricultural University, Anand on 05-04-2011.

Pigeonpea Hybrids – Present Status and Quality Seed Production*

P. P. ZaveriCEO & Proprietor

Biogene Agritech, Ahmedabad--------------------------------------------------------------------------------------------

Introduction:

Pigeonpea [Cajanus cajan (L.) Millsp.] is a short-lived perennial shrub but traditionally it is cultivated as an annual crop in Asia, Africa, Caribbean region and Latin America. It occupies important position in Indian agriculture. Globally Pigeonpea is cultivated on about 4.6 m hectare of land with annual production of 3.3 m tones and productivity of about 714 Kg per ha. India is the major pigeonpea growing country and it accounts for 3.5 m hectare area and 2.4 m tones of production. The pigeonpea area, production and productivity trends in India in last five decades shows that there was about 2% increase in the area per year but the yield levels were stagnated around 600-700 kg per hectare (Fig.1). There may be a number of climatic, edaphic and crop management factors for the low productivity but lack of high yielding cultivars appears to be an important factor underlying the constantly poor yield. The opportunities in horizontal increase in cultivated area are limited. The best remedy is to increase productivity for which we need high yielding cultivars and development of hybrids seems to be the best solution.

Pigeonpea is a hardy, widely adapted and drought tolerant crop. The short duration (100-140 days) cultivars are cultivated as sole crop while the medium duration (160-180 days) and long duration (> 200 days) landraces and cultivars are invariably grown as intercrop or mixed crop with other short duration crops. Besides its main use as dhal (dehulled dry split peas), its immature green seeds and pods are consumed as vegetable. The crushed dry seeds are fed to animals while green leaves form a quality fodder. The dry stems of pigeonpea make an excellent fuel wood. Pigeonpea is also grown on mountain slops to reduce soil erosion (Saxena et.al. 2006). The paper describes progress made in development of cytoplasmic-genic male sterility (CGMS) for hybrid breeding and its use in seed production technology.

I. CYTOPLASMIC - GENIC MALE STERILITY (CGMS) IN PIGEONPEA

Male sterility system in hybrid breeding:

Male sterility in plants is a phenomenon where the individuals are unable to produce through natural means because of their defective male reproductive parts. Such plants reproduced only on receipt of viable pollen from other plants either naturally or deliberately. The male sterility has played significant role in enhancing productivity in many crops (Sorghum, Maize, Pearl millet, Sunflower, Cotton, Rice, Vegetables etc.) facilitating hybrid seed production on large scale. -------------------------------------------------------------------------------------------------

* Presented during Agricultural Research Council Meet at Anand Agricultural University, Anand on 05-04-2011.

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Three kind of male sterility systems are reported and used.

1. Genetic 2. Cytoplasmic and 3. Cytoplasmic-genic (CGMS)

The genetic male sterility is controlled by genetic factors whereas in cytoplasmic system the genetic material in cytoplasm induces the sterility. The third kind is of male sterility is induced by interaction between genes in nucleus and cytoplasm which leads to specific biochemical events that hinders the normal process of pollen production. For effective use of CGMS, it is important that the expression of both the male sterility and its fertility restoration are stable over years and locations. All the three types are reported in pigeonpea but only CGMS is useful for commercial hybrid breeding. Presence of high heterosis coupled with high degree of out crossing and mechanism of large scale production of hybrid seed (Male sterility), are pre-requisites for commercial exploitation of hybrid vigor.

Pigeonpea flower morphology and natural out crossing:

The flowers of pigeonpea are hermaphrodite and its morphology and structure facilitate both self- as well as cross-pollination under natural conditions. In pigeonpea 24 insect species (mainly honey bees) have been reported to affect out-crossing and on an average 20% (0 to 70 % range) out-crossing is observed (Saxena et. al. 1990). In Gujarat the extent of natural cross-pollination in pigeonpea is reported to be 13.8 to 14.5 % (Savalia and Zaveri, 1994) which is sufficient, in our experience, to set enough pod loads on male sterile plants in seed production plot. The higher amount of natural crossing has always been treated as a constraint in breeding and maintenance of pigeonpea varieties causing lot of variation for most of the economic traits from farm saved seeds. This leads to low and inconsistent yield. This variation helped scientists to select a number of natural recombinants to develop good varieties. This opportunity was translated in developing commercial hybrids as out crossing is essential for hybrid seed production (Zaveri and Pathak, 1994). This together with availability of CGMS and high heterosis has provided required inputs for hybrid breeding in pigeonpea.

Heterosis in pigeonpea:

Presence of considerable amount of hybrid vigor in varietal crosses, over mid-parent and better-parent as well as over standard check variety have been reported in number of research articles for various economical characters in pigeonpea (Saxena and Sharma,1990). Besides the results obtained with GMS and CMS based hybrids, which are discussed below, are encouraging. All these reports suggest that with the help of stable CMS and available insect-aided natural out-crossing, the heterosis can be exploited at commercial level in pigeonpea.

Male sterility in pigeonpea:

A. Genetic Male Sterility (GMS):

All the GMS systems reported so far in pigeonpea have emerged from spontaneous mutations. The GMS systems reported in pigeonpea are summarized in Table-1. The ms1 gene with translucent anther was exploited and a first ever hybrid ‘ICHP-8’ was released by ICRISAT for cultivation in Central India in 1991. (Saxena et. al. 1992). Subsequently few more GMS based hybrids were released by ICAR. They are given in Table-2.

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The GMS based hybrids, though high yielding, could not reach farmers’ fields due to inherent constraints associated with maintenance of male sterility and hybrid seed

production on large scale. The major bottleneck is rouging of about 50% fertile segregates in female rows in seed production plot and associated problem of hybrid seed genetic purity if rouging is inefficient or delayed. Therefore, the system is not commercially viable, unless some seedling markers are available.

B. Cytoplasmic-genic male sterility (CGMS) – A major breakthrough:

The system was not naturally available nor were efforts made to isolate from natural existing varieties and breeding material. Efforts were made to induce CMS artificially as has been done in other crops. Reddy and Faris (1981) got an indication of maternal inheritance of male sterility in the progeny of cross Cajanus (formerly Atylosia) scarabaeoides X Cajanus cajan but the male sterility was found to be associated with a high degree of female sterility and other reproductive defects. ICRISAT initiated a special project in 1991 to developed CGMS and activities on induction on mutations through weak mutagens (Streptomycine, Mytomycin-c, Sodium azide, Ethidium bromide, mild X-rays etc.) and inter-specific hybridization were taken up by me as visiting scientist (Zaveri,1992). There was a clear indication in both the approaches that in the few lines isolated, the CMS is available. Later we could isolate few progenies from the segregating material derived from cross of C. sericeus with advance breeding line of pigeonpea, showing up to 100% male sterility (Ariyanayagam et. al., 1993). Besides conventional back crossing, a multiple genome transfer method was used (Ariyanayagam et. al., 1995) to stabilize CMS. This material was carried forward through additional hybridization and selection (Saxena et. al., 1996) which led to development of male sterile lines such as CMS 85010A, CMS 88034A and CMS 13091A. One more CMS source was reported by Tikka et. al.,1997 in cross of C. scarabaeoides with pigeonpea.

A protocol for induction of CMS in pigeonpea was developed for use by various participating scientists of ‘Consultative Group on Pigeonpea Cytoplasmic Male Sterility’ formed by ICRISAT in 1994 (Zaveri, 1994A). Approaches like germplasm screening, varietal hybridization, inter-specific and wide hybridization, induce mutations with steps to be followed to isolate CMS in pigeonpea are discussed in the protocol. The CMS activities at GSFC, Fertilizernagar resulted in development of CMS 67A line through inter-specific hybridization (Zaveri, 1994B, Zaveri and Donga 1998), which was later registered as plant germplasm with NBPGR, ICAR under INGR No. 04036 and national identity no. IC 296622. My experience in this work and also widely published literature in other crops indicates that the wide spread existence of this character suggest that it could probably be isolated in all crops if intensively sought (Zaveri, 2002).

Extensive efforts were initiated at ICRISAT, NARS and ICAR institutes to develop new CMS sources by placing pigeonpea genome in wild cytoplasm through wide hybridization. So far seven such systems have been reported in pigeonpea with varying degrees of success (Saxena et. al., 2101A). Out of these, A4 cytoplasm has shown promise because of its stability under various agro-climatic zones and availability of good maintainers and restorers. A brief on A1 to A7 CMS systems of pigeonpea is presented in Table-3.

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Maintenance and Fertility restoration of CGMS in pigeonpea:

A. Male sterility maintainers:

The A1, A2 and A4 CMS sources have been crossed with a wide variety of germplasm lines, varieties and breeding lines to access their reaction with respect to fertility behavior of resultant hybrids at ICRISAT (Saxena et. al., 2007) and at NARS. Several promising lines could be detected to maintain CMS with 95-100% male sterility. These maintainers had considerable variation with respect to morphological traits like, flowering, maturity, plant height and 100 seed weight. Few lines possessed resistance to wilt and sterility mosaic diseases. Many of them are converted into CGMS through repeated back crossing. It was observed by Saxena and coworkers at ICRISAT that majority of hybrids exhibited considerable intra-accession variation for pollen fertility and it could be due to differential inter-genomic or Cytoplasmic-genomic interaction. Such interaction usually involved complex genetic phenomenon like complementation, inhibition, epistasis and accumulation etc., which render the male fertility restoration control highly subtle and fragile. In pigeonpea, where a considerable level of heterozygosity in the germplasm exists due to natural out-crossing, the chances of getting such abnormal interaction are always high.

B. Fertility restoration of CMS:

In any CMS based hybrid technology, fertility restoration is a vital component. The observations on the F1 hybrids of A1, A2 and A4 cytoplasms indicated that in A1 and A2 types, the fertility restorers were available, but at low frequency and also perfect restoration was a problem. A high proportion of genotypes were heterogeneous for fertility restoration gene(s). In some genotypes there was only partial restoration and it may be confounded by environmental factors such as temperature and photo-period. So far, A4 cytoplasm system appears to be the best because of its stability and fertility restoration in F1 generation with plenty of pollen grains. The pollen load and pod set on F1 plants was as good as the control cultivars (Saxena et. al., 2007).

Over a period of time several new restorer parents have been identified at ICRISAT, GAU, S. K. Nagar and other NARS centers of ICAR for various cytoplasms with considerable variation for important agronomic traits in different maturity groups. They are currently in use to develop high specific combining ability hybrids.

C. Genetics of fertility restoration and cytological studies:

The genetics of fertility restoration has been studied in few combinations only for A4 cytoplasm (Dalvi et. al., 2008). They studied five crosses and reported that in three crosses a single dominant gene, while in one cross two dominant genes with duplicate gene action restored the fertility. In the fifth cross also two dominant genes, but with complimentary action governed the fertility. Further it was found that the Fr genes were randomly distributed in the germplasm.

Mallikarjuna and Kalpana (2004) studied the mechanism of Cytoplasmic-nuclear male sterility in pigeonpea derived from cross of C. cajan X C. acutifolius. They found two

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types of mechanisms. Type I CMS had partially or totally brown and shriveled anther morphology and the process of microsporogenesis was inhibited at the pre-meiotic stage. Type II CMS plants had pale white shriveled anthers and the breakdown in microsporogenesis was at the post meiotic stage after formation of tetrads. Dalvi et. al. 2008 studied the microsporogenesis in CMS lines of pigeonpea with A4 cytoplasm. They defined that the breakdown of tapetum in the main cause of male sterility.

CGMS hybrids in pigeonpea and hybrid vigor:

After development of stable CMS system and identification of restorers, several experimental hybrids were produced and evaluated at various institutes in India, which showed considerable hybrid vigor for grain yield in many cross combinations. At MAHYCO, Short, medium and late duration CMS based hybrids were evaluated in 2004. (Saxena el. al., 2010C). The results of selected hybrids are given in Table-4, which shows % gain of 29.9 to 87.9 in yield of hybrids over varieties. Kandalkar (2007) found that CMS based hybrids recorded standard Heterosis up to 156% for grain yield; whereas Saxena et. al. 2006, 2007 & 2010B reported yield advantage of 50 – 100% over popular varieties and local checks in short and medium duration hybrids in trials conducted during 2005 to 2009 on hybrids with A1, A2, and largely A4 cytoplasm. Many pipe line hybrids having brown seeds and white seeds are under evaluation at research centers and on farmer’s fields have shown very high yield compared to checks for seed yield and high level of resistance to wilt and sterility mosaic (Personal communication with Dr. Saxena, ICRISAT and Dr. Acharaya, SDAU, SK Nagar).

GTH-1

The GTH-1, a first white seeded hybrid from SDAU, SK Nagar was released by ICAR in 1994 for cultivation in Gujarat, which showed three years average yield raise of 42 %, 59% and 32% over the controls AKPH 4101, GT-100 and GT-101, respectively in state trials (Table-5). In front line demonstrations GTH-1 produced 25.3% more yield over popular varieties. The performance of GHT-1 in AICRP trials (Table-6) suggested 44% and 52% yield advantage of GTH-1 over GT-101 and UPAS-120, respectively. It’s female GT 288A has cytoplasm from C. scarabaeoides. GTR-11 is a restorer male line. However, the filed experiences on commercial planting are not satisfactory and encouraging due to restoration problems and it is under consideration to discontinue this hybrid (Personal communication with Dr. S. Acharya, SDAU, SK Nagar). It is an early maturity (140 days), indeterminate hybrid with large white seeds.

ICHP-2671

The other important hybrid taken up commercially is ICPH-2671 from ICRITSAT having high fertility restoration over years and locations, medium duration, indeterminate growth habit with spreading branching, purple pods, high resistant to wilt and sterility mosaic diseases and larger dark brown seeds (10.8 to 11.2 g/100 seed). It was evaluated in 43 multi-location trials during 2005-2008 and on an average recorded 35.85% superiority over Maruti, a popular variety. The results are shown in Fig-2. (Saxena et. al. 2010A). In ICRISAT-ICAR on-farm trials for three years (2007-2009), the superiority of hybrid varied from 23 to 37% (Table-7).

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The seed yield of this hybrid in on-farm trials in different cropping systems (Table-8) has shown an average rise of 37% (range 23-93%) over the check, Maruti. It has produced record yield of hybrid in the State of Maharashtra as given in Table-9 along with that of ICHP-2740. The seed color may cause a problem in acceptance of this hybrid. ICPH-2740

Yet another hybrid from ICRISAT, ICHP-2740 has eye catching performance coupled with high resistance to fusarium wilt and sterility mosaic. It is a medium duration, high branches, brown seeded hybrid. In multi-location 33 trials conducted for 4 years, this hybrid recorded 35.8 % superiority over the control (Fig.3). A large scale seed production of parents and hybrid has been taken up by some seed companies as the hybrid seed color and other futures are suitable and highly acceptable to farmers and seed industry. The parental seed of ICRISAT breed hybrids is shared with members of Hybrid Parent Consortium only under Private Public Partnership. Biogene Agritech is a member of this consortium.

Advantages of hybrid pigeonpea:

Hybrid cultivars in cereals (maize, sorghum and rice), oilseeds (castor, sunflower), Fiber crops (Cotton) and vegetables have revolutionized productivity worldwide. Hybrid pigeonpea also shares the advantages over varieties in the following areas.

1. Higher productivity and more biomass: Results of the trials conducted so far and discussed above give high confidence that the hybrids in pigeonpea would definitely help to raise productivity of the crop. The 30 days seedlings of hybrids are reported to produce 44% more shoot mass and 43% more root mass compared to pure line cultivars (Chauhan et. al. 1994). The hybrids are capable of producing large plants and more grain yield.

2. Enhance seeding vigor: Hybrid pigeonpea has a greater plant vigor compared to pure line cultivars (fig.4). The faster growth rate help the crops established firmly and develop its canopy faster. Also this makes hybrids more competitive to weeds and in inter-cropping especially during the initial crop growth stages.

3. Reduced seed rate: Studies (Chauhan et. al. 1994) have indicated that pigeonpea hybrids produced more primary and secondary branches with wider canopy and greater plasticity at plant population ranging from 16 to 66 plants per m2 without adversely affecting their grain yield. This implies that seed requirement of hybrids could be reduced to about 50% compared to the traditional varieties (Saxena et. al., 2006). Reduced seed rate will offset the higher cost of hybrid seed.

4. Greater disease resistance: Results of limited experiments conducted reveal that pigeonpea hybrids encounter the menace of diseases more efficiently than pure lines (Saxena et. al., 2006). It appears that in addition to the specific anti-fungal/viral resistance mechanism, the hybrids have an extra degree of genotypic plasticity (resilience) which helps them to tolerate and produce higher yields under stressed conditions compared to the pure lines.

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5. Greater drought tolerance: Hybrid pigeonpea by virtue of its greater root mass and depth compared to the varieties have greater ability to draw water from soil profile from deeper soil depths. This also helps the hybrids to tide over the drought conditions prevailing during the different phases of the crop growth.

II. SEED PORDUCTION TECHNOLOGY USING CGMS IN PIGEONPEA

Availability of genetically pure seed of improved cultivars is crucial for realizing productivity. An efficient seed production system that could provide quality seeds at

economically viable cost is the backbone of any hybrid breeding technology. The benefits of new hybrids can not be fully realized until sufficient quantity of genetically pure seeds are commercially produced and sold at a cost affordable to the farmers.

To date, considerable information has been generated on seed production technology of parents and hybrids using GMS and CGMS based seed production as discussed below. The most of our experience on hybrid seed production has come from genetic male sterility. As such the seed production would not differ much in the field except that related to type of male sterility system.

Isolation distance:

Pigeonpea is an often cross-pollinated legume and show considerable natural cross pollination. The extent of out-crossing in the crop is determined by insect activity, which varies from place to place (Saxena et. al., 1990). Therefore, it is difficult to specify an isolation distance that would be effective at every location. However, at present some safe and standard guidelines are essential to maintain the purity of hybrids and their parents. Isolation distance for the seed production of pure line varieties recommended by different scientists range from 100 to 400 m. Saxena (2006) has recommended an isolation of 500 m for quality CMS based hybrid seed production. With a view to avoid the chances of contaminations and produce high quality seed, it is suggested that specific studies be conducted using recently developed CMS lines. In the mean time, we continue to produce seeds of hybrids and their parents at a minimum isolation distance of 300 – 400 m.

Seed production of parental lines:

The purity and quality of hybrid seed is directly related to purity and quality of breeder seed which in turn depends on high purity nucleus seed. The details are explained by Saxena (2006). The parent seed production of A, B and R lines is briefly discussed below.

A-line seed multiplication: At the initial stage the nucleus seed of A-line is produced by growing both A and B lines inside an insect proof cage (Mosquito nets). Single plants of A and B lines confirming their characters are selected and paired crosses made between them. The crossed seed set on the A-line plants and selfed seed on the B-line plants are harvested separately. The seeds of both the lines harvested so become the pure mother stock for further use to produce breeder seed.

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For large quantity of Breeder and foundation seed production in isolation, the row ration of 4 A-lines :1 B-line has largely been found to be useful at ICRISAT and at SDAU, SK Nagar. Additional planting of B-lines around seed plot would be beneficial to augment pollen supply through bee activities. Also if few B-lines are planted about 7-10 later in and around seed plot, this will enhance pollen supply from these late flowering B-lines as normally farmers avoid harvesting of pods from B-line, which resulted in poor flower production and shortage of pollen. The experimental data reveals that a seed yield of 1100 Kg/ha A-line was harvested under 4:1 row ration of ICPA 2039 (Saxena et. al., 2006). In other CMS ICPA-2032, seed yield of 1555 Kg/ha A-line was harvested (Saxena et. al., 2010C). Perfect rouging of A and B lines is essential. A and B lines do not differ in morphological traits except that A-line is CMS and we need to inspect each plant with respect to sterile anthers by opening flowers. This is a crucial and vigilant exercise and

should be done immediately and faster as soon as flowering is started to remove any fertile plant in A-line carefully.

B and R-line seed production: These lines are like any pure line variety and their seed production can be done following standard procedure of varietal seed multiplication. It is suggested that care should be taken up in production of nucleus seed for which the plots of A and B lines be grown in safe isolation. Critical rouging is taken up. At maturity, we need to harvest about 100 true to type plants separately from the central portion of field. The seed so collected is to be planted as plant to progeny rows in isolation next season and seed bulked to get basic seed stock to initiate breeder seed production.

Hybrid seed production in pigeonpea with CGMS:

Enough experience has been gathered for hybrid seed production with GMS. This has served as a good guideline for hybrid seed production using Cytoplasmic male sterility. As on to day no specific seed production technology is recommended for the purpose. The foundation seed of A-line and R-line of a hybrid is the source of hybrid seed production by growing them in a row ration of 4 A-lines : 1 R-line in field having 300-400 m isolation from other pigeonpea crop. Additional rows of R-line around seed plot help more pollen availability and better pod set on A-line to realize more hybrid seed yield (Fig.5). Even few late planted R-line in and around seed plot would prolong flowering and pollen source. The pollinating insects visit the male and female flowers in a random fashion and in the process collect pollen from fertile plants and carry out hybridization on the male sterile plants. Where the insect activities are abundant, more rows of A-lines (6 to 8) can be accommodated. The training of seed producing farmers and seed labors in identification of sterile and fertile plants as well as off-types in very much essential for efficiently and timely removal of fertile plants from within female rows to produce high purity seed. The rouging and strict crop monitoring is a critical aspect of hybrid seed production and rouging should be done at seedling and flowering stage. It is my experience that in Gujarat, if a profusely flowering crop of mustard is in nearby field of the hybrid or parent seed plot of pigeonpea, it adversely affects pod set on male sterile plants as bees mostly visit mustard crop. Such care in selecting seed plot is essential. On maturity the R-line should be harvested first to help avoid any mixture of its seed with hybrid seeds.

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Experiences and results of hybrid seed production programs in pigeonpea:

Lot of experience is generated on hybrid seed production based on CMS at ICRISAT and other locations in India. Their published repots have indicated that the hybrid seed of 1083 Kg/ha was obtained from 4 :1 row ration planting of A and R line (Saxena et. al., 2010C) during 2005 rainy season. During 2007 Kharif season, ICHP-2671 hybrid seed plots were arranged by few seed companies in three states of India and hybrid seed of 625 to 2267 Kg/ha was harvested as shown in Table-10 (Saxena et. al., 2010B). The hybrid seed production data suggest that it can be taken up successfully with good yield in area of high bee activities without much problem and good quantity of hybrid seed can be harvested. The private seed companies needs to be involved in this activity under Public Private Partnership models (Zaveri et. al. 2010) for faster spread the hybrid technology and seed to farmers for raising productivity of this important legume.

Cost of production cost of hybrid seed:

The cost of hybrid should not be high so that small and medium farmers can afford it. If the hybrid is advantageous in real terms with wilt and sterility mosaic diseases, fitting their cropping pattern, farmers do not hesitate to pay higher price for seed. Some efforts were made by SDAU, SK Nagar (personal communication Dr. S. Acharya) to work out costing of seed production of CMS hybrid. The information is given in Table-11. It was found that with hybrid seed yield of 1886 Kg/ha and procurement price of Rs. 50 per kg, the gross income was Rs. 94300.00. Added to it the realization of Rs. 4775.00 from sale of 319 Kg/ha seed obtained from male rows at the sell price of Rs. 15 per kg, the total gross income of seed came to Rs. 99085.00. From this the cultivation expenditure of Rs. 17150.00 is deducted than the net realization was Rs. 81935.00 from the one hectare of hybrid seed production plot.

We had paid Rs. 60 per kg procurement price to a farmer in 2007, who produced 850 Kg hybrid seed of ICPH-2671 in Gujarat for us (Table-10). The hybrid seed cost seems to be reasonable and farmers can easily absorb. Only concerned is we need to take extra vigilance and care to produce high genetic purity and quality seed of high yielding hybrids.

Morphological Characters of pigeonpea hybrids and their parents:

The distinguished morphological characters of parental lines and hybrids are important to facilitate rouging operations in standing seed plot as well as conduction ‘Grow Out Tests’ for judging genetic purity of seed produced. The attributes of three promising hybrids viz., ICHP-2671, ICPh-2740 and GTH-1 are presented in Table-12, 13 and 14, respectively.

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R&D inputs required in hybrid development and seed production:

The following are few areas which need attention of all R&D institutes for making the hybrid breeding in pigeonpea more dynamic and rewarding.

1. Diversification and widening genetic base of parents and development of hybrids for specific agro-climatic conditions.

2. Resistance building in parents to major diseases like wilt and sterility mosaic.3. Fine tuning of seed production technology for different regions.4. Development of parameters for seed quality assessments of hybrid and parents

especially through biotechnology tool to hasten GOT in laboratory.5. Expand research and development base involving SAUs, ICAR, ICRISAT and

private sector for efficient and fast Lab to Land achievements under public private partnership.

6. Encourage capacity development of partners in hybrid research and development.

7. Use of biotechnology including molecular markers to enhance hybrid breeding efficiency.

8. Incorporation of genetic markers associated either with fertile or sterile plants to precise the work of rouging in seed production plots even at seedling stage.

Looking Ahead:

The experimental results so far obtained with hybrid breeding in pigeonpea have clearly demonstrated that in pigeonpea commercial exploitation of heterosis is feasible and advantageous. This coupled with performance of hybrids observed in on-farm trials are exciting. Besides, we have good information and data on seed production technology. All these have proved that hybrids in pigeonpea has a potential of breaking the barriers of stagnated yield in this precious protein reach legume for country like India to circumvent malnutrition. Few refinements in the existing hybrids and seed production aspects and additional R&D inputs suggested would further boost the pigeonpea hybrid technology. At present ICAR, SAUs and ICRISAT are actively involved in technology improvement and transfer to various development agencies. A time has come that public sector alone can not take all responsibilities and activities and therefore private sector need to be associated for speedy transfer of technology. The private sector is a major player in seed production, supply and marketing in India. They have high strength and better perception of farmer’s requirements. Public sector system needs to correct their vision about private sector and be more professional. IPR guidelines of ICAR provide statutory autonomy to institutes to enter into partnership with private sector.

Acknowledgement:

Thanks to Dr. K. B. Saxena, Principal Scientist, ICRISAT and Dr. S. Acharya, Research Scientist (Pulses), SDAU, S.K. Nagar for the information and data provided.

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Dalvi, V.A., Saxena, K. B., Luo, R. H. and Li, Y.R. (2010) An overview of male sterility systems in pigeonpea [Cajanus cajan (L.) Millsp.]. Euphytica. Published on line on 11 Feb. 2010.

Mallikarjuna N., and Kalpana, N. (2004). Mechanism of cytoplasmic nuclear male sterility in pigeonpea wide cross Cajanua cajan X C. acutifolius. Indian J. Genet. 64: 115-117.

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Saxena, K. B., Sultana, R., Mallikarjuna, N., Saxena, R. K., Kumar, R. V., Sawargoankar, S. L. and Varshney, R. K. (2010A). Male sterility systems in pigeonpea and their role in enhancing yield. Plant breeding. 129: 125-134.

Saxena, K. B., and Nadarajan, N. (2010B). Prospects of pigeonpea hybrids in Indian agriculture. Presented at the ‘Third National congress on plant breeding and genomics’. TNAU, Coimbatore, 7-9, July, 2010.

Saxena, K. B., Kumar, R. V., Dalvi, V.A., Pandey, L. B., and Gaddikeri, G. (2010C). Development of cytoplaasmic-nuclear male sterility, its inheritance and potential use in hybrid pigeonpea breeding. Journal of heredity advance access, Published 9 April, 2010.

Tikka, S. B. S., Parmar, L. D. and Chauhan, R. M. (1997). First record of Cytoplasmic-genic male sterility system in pigeonpea [Cajanus cajan (l.) Millsp.] through wide hybridization. GAU res. Journal. 22: 160-162.

Zaveri, P. P. (1992). Studies on induction / identification of cytoplasmic male sterility in pigeonpea. A report of work done at ICRISAT during May 1991 – May 1992 (Limited circulation).

Zaveri, P. P. (1994A). Protocol for induction and identification of Cytoplasmic male sterility system in pigeonpea. Developed for ‘Consultative group on Cytoplasmic male sterility ICRISAT’. Gujarat State Fertilizer Company Limited, Fertilizernagar, Dist. Vadodara, Gujarat State, India (Limited circulation).

Zaveri, P. P. (1994B). Cytoplasmic male sterility in pigeonpea at GSFC – Present status and future plans. Presented at the ‘First consultative group meeting on CMS in pigeonpea’ held at ICRIAST, Patancheru, A. P. India. 26-27, July 1994.

Zaveri, P. P. (2002). Potential methodologies for developing Cytoplasmic-genic male sterility in pigeonpea. Presented at the training course on ‘ Pigeonpea improvement with special emphasis on CMS based hybrid breeding technology’ organized at ICRISAT, Patancheru, A.P. India. 16-18 Sept., 2002.

Zaveri, P. P. and Donga, P. P. (1998). Cytoplasmic-genetic male sterility in pigeonpea. Presented at the ‘Vth Consultative group meeting on CMS in pigeonpea held at NDUAT, Kumarganj (Faisabad). 16-17 March, 1998.

Zaveri, P. P. and Pathak, A.R. (1994). Pigeonpea In ‘ Hybrid Cultivar Development’ (Banga, S. S. and Banga, S. K. eds) Narosa Publishing House, New Delhi – 110 017, India. pp 438-450.

Zaveri, P. P., Lavanya, C. and Hegde, D. M. (2010). Public Private Partnership for Increasing Productivity in Castor (Ricinus communis L.). Lead paper presented at National Symposium on Research and Development in Castor: Present Status and Future Strategies. Organized by Indian Society of Oilseeds Research, Directorate of Oilseeds Research, Rajendranagar, Hyderabad - 500 030. 22-23, October, 2010.

0—0-0-0-0-0-0-0-0-0-0-0-0-0

Source: Saxena et. al., 2010B

Fig. 3: Performance of hybrid ICPH-2740 over four years in 33 trials conducted in India, 2008.

Source: Saxena et. al., 2010A

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Fig. 4: Comparison of seeding vigor in hybrid and control.

RRRRRRRRRRRRRRRRRRRR

RR

RRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR

RR


RRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR

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RRRRRRRRRR RRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR RRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR













RR

RRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR

RR


Fig. 5: A standard field lay out of hybrid seed production in pigeonpea

A = CMS lines (A-line) R = Restorer lines (R-line)

Table-1: A summary of genetic male sterility systems reported in pigeonpea.

S. No. Author Gene symbol

Remarks

1 Deshmukh (1959) - MST was associated with female sterility

2 Reddy et. al. (1977) - 7 types of floral variants with varying degree of MST recorded

3 Reddy et. al. (1978) ms1 Translucent male sterile anthers4 Dundals et. al. 1982) - Photo insensitive MST mutant5 Saxena et. al. (1983) ms2 Brown arrow-head shape anthers, non-

allelic to ms1 6 Verukar & Singh (1997) - Single recessive gene control 7 Wanjari et.al. (2000) - Single recessive gene control8 Saxena & Kumar (2001) ms3 Under developed anthers, non-allelic

to ms1 and ms29 Venkateswarlu et.al. (1981) - MST linked to obcordate leaf type

10 Pandey et.al. (1994) - MST linked to obcordate leaf type11 Saxena et. al. (1981) - Partial MST with sparse pollen

production 12 Gupta and Faris (1983) - Recessive gene control

Adapted from Saxena et. al., 2010A

Table-2: GMS based hybrids released in India (Saxena et. al., 2010A).

Name of hybrid

Year of release

Institution who developed hybrid

Days to maturity

Grain yield Kg/ha

Yield superiority over check (%)

ICHP-8 1991 ICRISAT 125 1780 30-41 (UPAS 120)PPH-4 1993 PAU, Ludhiana 137 1930 14 (UPAS 120)CoH-1 1994 TNAU, Coimbatore 117 1210 19-22 (Vamban 1)CoH-2 1997 TNAU, Coimbatore 125 1050 35 (Co 5)AKPH-4104 1997 MPKV, Akola 135 NA 64 (UPAS 120)AKPH-2022 1998 MPKV, Akola 190 NA 25-35 (BDN-2)

Table-3: Cytoplasmic male sterility systems in Pigeonpea

S.No. Cytoplasm type

Cytoplasm donor source

Main characters Reference

1 A1 Cajanus sericeus Not stable in low temperature in short duration types, In

Zaveri, 1992 and 1994A, Ariyanayagam et.al. 1993

long duration maturity stable, Gives good heterosis, Limited maintainers.

& 1995; Zaveri & Donga, 1998; Saxena et. al., 2010

2 A2 C. scarabaeoides Stable CMS but inconsistency in restoration,

Zaveri, 1992; Saxena & Kumar, 2003; Tikka et.al., 1997

3 A3 C. volubilis Not in use due to fertility restoration problems

Wanjari et.al., 2001

4 A4 C. cajanifolius Best CMS from close relative, Good number of maintainer and restorers, Stable over locations and years, Good pod set and yield in hybrids

Saxena et. al., 2005

5 A5 C. cajan(Cultivated type)

Cytoplasm from cultivated type, maintainer is wild type,

Mallikarjuna and Saxena, 2005

6 A6 C. lineatus Natural out cross in wild rows, Perfect maintainer available

Saxena et. al., 2010A

7 A7 C. platycarpus Tertiary gene pool, cross incompatible, hormone aided pollination and embryo rescue to get hybrid, Maintainer & restorer available

Saxena et. al., 2010A

Saxena et. al., 2007. and Saxena et. al., 2010

Table-3A: List of important CGMS and R-lines (incomplete list)

S. No.

Institute GCMS lines R-lines Remarks

1 ICRISAT ICPA – 2086ICPA – 2102ICPA – 2078ICPA – 2043ICPA – 2046

ICPR –3467ICPR –3963ICPR –3801ICPR –3349ICPR –3374

CGMS and R lines possess resistance to wilt and/or sterility mosaic diseases. They

ICPA – 2086ICPA – 2086ICPA – 2086ICPA – 2086ICPA – 2086

ICPR –3516ICPR –3405ICPR –3519ICPR –3407ICPR –3426ICPR –3337ICPR –3463ICPR –3470ICPR –2679

have A4 cytoplasm and shown stability of male sterility trait.

2 SDAU, SK Nagar

CMS GT 33A/GT 33 BCMS GT 87A/GT 87BCMS GT100A/GT 100BCMS GT 288A/GT 288BCMS GT 301A/GT 301BCMS GT 306A/GT 306BCMS GT 308A/GT 308BCMS GT 402A/GT 402BCMS GT 404A/GT 404BCMS GT 502A/GT 502BCMS GT 289A/GT 289BCMS GT 310A/GT 310BCMS GT 501A/GT 501BCMS GT 505A/GT 505B

GTR 1, GTR 8,GTR 9, GTR 10,GTR 11, GTR 2,GTR 3, GTR 4,GTR 5, GTR 6,GTR 52, GTR 7,GTR 35,GTR42,GTR 43,GTR 55

Character information not available.

3. BiogeneAgritech

Code-101, Code-202, Code-303

Code-R-1,R-2, R-3, R-4, R-5, R-6, R-7, R-8, R-9

White seeded line, few resistant to wilt and SMD

4 GFSC Ltd.,Fertilizernagar

CMS-67A - Registered with NBPGR

5. Other institutes and SAU

No information is available but many SAU centers including IIPR, Kanpur as well as about 30 private seed companies are working with hybrid pigeonpea and they shall have good breeding lines (A, B and R lines).

Table-4: Yield (kg/ha) of some selected short, medium and long duration hybrids tested at six locations in trials conducted by MAHYCO, during 2004 rainy season. ( Source: Saxena et. al., 2010C)

Table 5: Performance of pigeonpea hybrid GTH-1 in Gujarat state during Kharif, 2000-01 to 2003-04 [Grain yield kg/ha]

Season & Name Location Varieties C.D CV

Year of testing

of Trial

. at 5%

%GHT-1(SKNPCH-

10)

AKPH-4101 (C)

GT-100 (C)

GT-101 (C)

Kharif-2000

PHT S.K. Nagar 2827 1224 1218 - 161 4

Mean 2827 1224 1218 -Kharif-2001

SSHT S.K. Nagar 1852 1219 1431 - 242 10

Ladol 644 679 707 - NS 15Anand 450 825 770 - 266 35

*Mean 1774 1041 1119 -

Kharif-2002

LSHT S.K. Nagar 2057 1543 - 1381 111 14

Anand 2106 1759 - 1562 290 10Bharuch 1906 1662 - 1759 378 11Vadodara 849 548 - 540 238 21Derol 2547 1666 - 1782 369 11Navsari 2346 1698 - 2022 158 5Mean 1969 1479 - 1508

Kharif-2003

LSHT S.K. Nagar 2537 1444 - 1620 236 9

Bharuch 1144 1130 - 1017 139 7Vadodara 1111 868 - 910 205 9Junagadh 2516 2161 - 2344 218 6Derol 938 608 - 573 212 19Navsari 1013 390 - 448 158 19Mean 1543 1100 - 1152Mean (2002, 03)

1756 - - 1330

Overall Mean 1760 1240 - -% increase over

42 59 32

* Results not considered due to high CV %Source Dr. Acharya S. SDAU, SK Nagar (personal communication)

Table 6: Location-wise mean performance of GTH 1 in Central Zone.

Sr. No. Name of Trial Locations Name of EntryGTH 1 GT 101 UPAS 120

1. IHT (E) S. K. Nagar 1167 1427 1177

Rahuri 3912 1933 2271Navsari 816 625 348Khargone 878 447 339Mean 1693 1108 1033*Mean 2539 1680 1724

2. AHT (E) S. K. Nagar 1566 1487 986Rahuri 2520 1788 2034Navsari 1389 798 486Khargone 1623 1031 1038Mean 1775 1276 1136*Mean 2030 1411 1332% increase over 44 52

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Table-7: Performance of hybrid ICPH-2671 in on-farm trials in Maharashtra State, 2007-2009.

Year Trials Area (ha) Plot size (ha) Hybrid yield (Kg/ha)

% Gain

200720082009

Total/mean

29782112

923

1326143

317

0.2 to 0.40.2 to 0.40.2 to 3.2

-

178310251400

1403

293723

30


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Table-8: Performance of hybrid ICPH-2671 in OFTs in different cropping systems (2008)

System No. of demos.

Area (ha) Yield Kg/ha % IncreaseHybrid Maruti

SolePP + MaizePP + SoybeanPP + CottonPP + Groundnut

6378729218

220171283

11208291250730916

913593648648779

2339931318


Table-9: Record yields produced by hybrid pigeonpea farmers in Amravati and Yeotmal district of Maharashtra State in 2009.

Name and village Hybrid Area (m2) Yield (Kg/ha) % GainHybrid Check

SB Kale, Salod ICPH-2671 450 3956 2044 94

PK Satav, NimgoanDV Chopade, KothodaYS Shrotri, Tamoli

ICPH-2671ICPH-2671ICPH-2671

1012450450

395146673889

246935562278

603171

RK Warekar, P’KawadaVB Kadam, TamoliBK Warekar, P’Kawada

Mean

ICPH-2740ICPH-2740ICPH-2740

450338338

414844444444

4214

296326672963

2706

406750

56Source: Saxena et. al., 2010B

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Table-10: Seed production of hybrid ICHP-2671 (A X R) in different locations during rainy season 2007.

Source: Saxena et. al., 2010BTable-11: Cost of Cultivation and economics of hybrid seed production in pigeonpea.

Expenditure:

Sr. No Particulars Rates Cost (Rs.)1. Seed cost Female 18 kg @ Rs.50 900.00

Male 3kg @ Rs.50 150.002. Cultivation 3 hrs @ Rs.400 1200.00

3. Sowing 2 hrs @ Rs.400 800.004. Fertilizer Dose 25:50:00 NPK kg/ha 1000.005. Irrigation (Five) 5 @ Rs.600 3000.006. Insecticides and

PesticidesAs required 2000.00

7. Rouging charges 3 @ Rs.400 1200.008. Harvesting 12 labour @ Rs. 100 1200.009. Thrashing a. 2 labour @ Rs. 100 200.00

b. 3 hrs thrasher @ Rs. 400 1200.0010. Grading 5 labour @ Rs. 100 500.0011. Packing charges 380 bag @Rs 10 3800.00Total Expenditure per ha. 17150

Earning:

Particulars Rates (Rs/kg) Income (Rs.)Hybrid seed production 1886 kg/ha 50 94300.00Male seed production 319 kg/ha 15 4785.00Total Income 99085.00

Profit (Rs.) : 99085.00- 17150.00 = 81935.00 Seed cost of hybrid seed = 9.09 or Rs 9.00/kgProfit /kg of seed = Rs 43.44 i.e. Rs. 43.00 per kg hybrid seed ---------------------------------------------------------------------------------------------Source: Dr. S. Acharya, SDAU, SK Nagar, Personal communication

Table-12: Characters of hybrid pigeonpea ICPH-2671

Characters Female (A-line)ICPA - 2043

Male (R-line)ICPR - 2671

HybridICHP-2671

Days to 50% flowering 110-115 122-128 119-121

Days to maturity 158-165 180-185 168-176

Plant height (cm) 170-180 215-225 238-260

Growth habit Indeterminate Indeterminate Indeterminate

Branching pattern Spreading Spreading Spreading

Stem color Green Green Green

Leaf shape Lanceolate Lanceolate Lanceolate

Flower color Light yellow Yellow with light streaks

Yellow with red streaks

Pod form Cylindrical Cylindrical Cylindrical

Pod color Green Green with brown streaks

Green with purple streaks

Seeds pod-1 3.5-4.2 3.7-4.0 3.8-4.1

100-seed mass (g) 11.2-11.8 10.7-12.3 11.4-11.8

Special characters Wilt and Sterility mosaic resistant

Source: ICRISAT

Table-13: Characters of pigeonpea hybrid, ICPH-2740

Character Female (A-line) ICPA 2047

Male (R line)ICPR 2740

HybridICPH 2740

Days to 50% flowering 115-127 122-128 125-130Days to maturity 165-185 180-185 176-189Plant height (cm) 170-235 215-225 230-260Growth habit Indeterminate Indeterminate IndeterminateBranching pattern Spreading Spreading SpreadingStem color Green Green Green

Leaf shape Lanceolate Lanceolate LanceolateFlower color Yellow with light Purple

streaks Yellow with light streaks

Yellow with light red streaks

Pod form Cylindrical Cylindrical CylindricalPod color Green with purple

streaksGreen with brown streaks

Green pod Brown Streaks

Seeds pod-1 4.0-4.3 3.7-4.0 3.7-4.1Seed color Brown Brown Brown

100-seed mass (g) 11.6-12.2 10.7-12.3 11.3-11.6Dal color - Yellow YellowDal taste - Acceptable AcceptableSpecial characters Wilt and Sterility mosaic resistant Source: ICRISAT

Table -14: Characters of GTH-1 hybrid pigeonpea

1. MAJOR CHARACTERS HYBRID

GTH-1

FEMALE

CMSGT-288A

MALE

GTR-11

2.* PLANT : BRANCHING PATTERN SPREADING SPREADING BUSHY

3.* GROWTH HABIT INDETERMINATE INDETERMINATE DETERMINATE

4.* PLANT HEIGHT (CM) TALL (160-180) MEDIUM (140) SHORT (90)

5. STEM : ANTHOCYANIN COLOUR ABSENT ABSENT ABSENT

6. LEAF : SHAPE OBLONG OBLONG OBLONG

7. LEAF : PUBESCENCE ABSENT ABSENT ABSENT

8. TIME OF FLOWERING (DAYS) EARLY (85-95) EARLY (85-90) EARLY (95-100)

9. BASE COLOUR OF PETAL YELLOW YELLOW YELLOW

10.* PATTERN OF STREAKS ON PETAL SPARSE SPARSE ABSENT

11. POD COLOUR GREEN WITH BASE STREAKS

GREEN GREEN WITH

BLACK STREAKS

12. POD PUBESCENCE ABSENT ABSENT ABSENT

13. POD STICKINESS PRESENT PRESENT PRESENT

14. POD CONSTRICTION SLIGHT SLIGHT SLIGHT

15. SEED COLOUR WHITE WHITE WHITE

16. SEED COLOUR PATTERN UNIFORM UNIFORM UNIFORM

17. SEED SHAPE OVATE OVATE OVATE

18. SEED SIZE (G/100 SEED) LARGE (10.5) LARGE (9.8) LARGE (10.1)* Useful markers for GOT

Contd. …..

Table -14: Contd… (Characters of GTH-1 hybrid pigeonpea)

OTHER CHARACTERS HYBRID

GTH-1

FEMALE

CMSGT-288A

MALE

GTR-11

1. LEAF LET SIZE MEDIUM MEDIUM MEDIUM

2. LEAF TIP POINTED POINTED POINTED

3. LENGTH OF PETIOLE MEDIUM MEDIUM MEDIUM

4. NUMBER OF PODS PER CLUSTER MEDIUM (3-5) MEDIUM (3-5) MEDIUM (3-5)

5. HILUM SHAPE OBLONG OBLONG OBLONG

6. SEED STROPHIOLE PRESENT PRESENT PRESENT

7. SEED EYE COLOUR LIGHT ORANGE LIGHT ORANGE LIGHT ORANGE

8. MATURITY DURATION (DAYS) EARLY (135-145) EARLY (140) EARLY (145)

Source: Dr. S. Acharya, SDAU, SK Nagar, Personal communication

pigeonpea hybrids lecture pp zaveri

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