1Division of Genetics, Indian Agricultural Research Institute, New Delhi-110012, India Email: Shyamsinghyadav@yahoo.com
2CSIRO Plant Industry, Private Bag 5, Wembley, WA 6913, Australia
3 USDA-ARS, 303 Johnson Hall, Washington State University Pullman, Washington 99164-6434 USA
4 NSW Agriculture, Tamworth Canter for Crop Improvement, Australia
5Agriculture Victoria, Horsham, Victoria, Australia
6 Center for Legumes in Mediterranean Agriculture, University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009
Investigations were undertaken with two major objectives, viz. to explore opportunities for improving adaptation of large-seeded kabuli chickpea for drought-prone environment, and to identify extra-large-seeded kabuli chickpea genotypes for cultivation in dry areas. To develop the segregating populations, three sets of cross combinations were formulated, viz. 1. extra-large-seeded wilt resistant kabuli variety BG 1073 was crossed with extra large-seeded kabuli varieties, 2. variety BG 1073 was crossed with large-seeded varieties, and 3. variety BG 1073 was crossed with medium large seeded kabuli varieties. The segregating populations, viz. F2-F6, were advanced under moisture stress environments in multiple sick-plots. Advanced yield testing was also carried out in rainfed conditions to evaluate the relative performance of the newly developed superior genotypes from 2000 to 2003. The relative seed yield of the new extra-large-seeded genotypes, when compared with the new large-seeded, the medium-seeded genotypes and the extra-large-seeded exotic and local control varieties, showed significant superiority and adaptation under water-limited environments. Under rainfed conditions, the new extra-large-seeded genotypes also showed significant superiority in respect of number of branches, number of pods and biomass production over all the extra large seeded control lines. The findings clearly indicated that the seed yield, along with number of branches, number of pods, and biomass, of new extra large seeded lines increased simultaneously and played a crucial role in the improvement of drought tolerance because these three traits were very poor in the extra-bold-seeded control lines. These three traits may have improved due to new recombinations of the gene pool during the hybridization and selection strategy adopted in the segregating populations. Based on these findings it was concluded that the poor adaptation to drought prone environments of the extra-large-seeded kabuli types could be genetically enhanced if strategic selection of parents and systematic approaches are adopted during hybridization and generation advancement. It was also concluded that agronomic traits such as the number of branches, number of pods, total biomass production and medium-early maturity played a crucial role in the drought stress tolerance in chickpea.
Strategic breeding with simultaneous selection for improvement in number of branches, number of pods, large seed size and high seed yield can lead to adaptation of Kabuli chickpea to drought-prone environments.
Key words
Moisture stress, Kabuli chickpea, gene pool, recombinations, selection, generation.
Unpredictable moisture deficits during crop growth are a major constraint to productivity, adaptation and stability of crop performance throughout the world. Due to this single factor the annual yield losses are globally very high, ranging from 30-40 percent. Along with drought, soil-borne diseases are also associated with crop losses at different growth stages. At present more than 80 % of the area of chickpea worldwide is rainfed, making chickpea crop economically unviable under rainfed agroecosystems.
It is considered essential that to enhance the adaptation of chickpea varieties to drought prone environments both genetic and agronomic approaches are needed. The adaptation of a crop variety is the ability of that variety to perform and produce to its maximum in a particular environment. Currently most of the cultivated extra-bold-seeded kabuli varieties of are poorly adapted to drought-prone environments. However, the small-seeded desi chickpeas are better suited to drought- prone environments than kabuli types. The present investigation was initiated to enhance extra-large-seeded kabuli chickpea adaptation to drought conditions through breeding (Yadav et al., 2003).
The material for present investigation consisted of selected parental lines i.e.BG 267, BG 1003, BG 1048, BG 1053, BG 1072, BG 1073 and BG 1082 of Indian origin and extra-bold-seeded control lines, viz commercially-marketed Canadian, Australian and American cultivars. Prior to the present investigation the hybridization between extra-large-seeded types, large seeded types and medium-large seeded types was carried out to develop segregating populations. Progenies from six promising crosses, viz. (i) BG 1073 x BG 1082, (ii) BG 1073 x BG 1072, (iii) BG 1073 x BG 1048, (iv) BG 1073 x BG 1003, (v) BG 1073 x BG 267, and (vi) BG 1073 x BGD 70 were selected for advancement under rainfed conditions. The advanced breeding lines from these six crosses were included in the yield evaluation testing along with five checks, two of Indian origin and three of exotic origin. Thus, the experimental material consisted of 11 genotypes including five checks.
The experiment was planted in a replicated randomized block design with 4-row plots, having 40 cm row to row and 20 cm plant to plant distance with 5 m in length. The experiment was conducted under rainfed conditions at the experimental station, Indian Agricultural Research Institute, New Delhi, India, during crop season 2001-02 and 2002-03. Single plant observations were recorded for agronomic traits, viz. plant height, number of branches, days to maturity, number of pods, 100-seed weight, biomass and seed yield. The seed yield per plot was also recorded. Statistical analysis was carried out by pooling the data of both the years through SPAR-I program. The relative comparison of new genotypes of each group with the best control line was investigated.
The data for different yield traits was pooled over the two seasons and presented in Table 1. The performance of the newly developed extra-large-seeded lines was significantly better than all the other new genotypes of large and medium seeded groups and the extra-bold-seeded control varieties. The seed yields of the six new genotypes were 3060, 3125, 2840, 2230, 2050 and 2080 kg/ha, respectively, compared to the yields of the check varieties that were 860, 950 and 1015 kg/ha for the Canadian, Australian and American varieties, respectively. The results showed a significant yield superiority of the new extra-large-seeded genotypes over checks. The performance of these genotypes and the control lines in respect to the number of branches, number of pods and biomass production were more or less similar. This trend indicated that in the overall performance of the new extra-large-seeded genotypes these three traits played a significant role in the adaptation to drought environment and in the increase of productivity.
Table 1: Superiority of yield and its contributing traits of newly developed extra large seeded chickpea genotypes under rainfed agro ecosystem in 2001-02 and 2002-03
CROSS |
Pt. Ht. (cm) |
Days to maturity |
No. of Branches |
No. of Pods |
100 seed weight (g) |
Biological yield (g) |
Seed yield (kg/h) |
Yield superiority percent over best check of the group |
Extra large seeded |
||||||||
BG 1073 X BG 1082 |
62.4 |
150 |
40** |
115** |
48.5 |
195.5** |
3060** |
201 |
BG 1073 X BG 1072 |
65.0 |
150 |
45** |
130** |
48.8 |
210.4** |
3125** |
207 |
Canadian [ELS] Check |
55.3 |
145 |
15 |
42 |
50.2 |
48.2 |
860 |
|
Australian [ELS] Check |
56.2 |
145 |
20 |
48 |
51.3 |
55.6 |
950 |
|
American [ELS] Check |
64.5 |
150 |
21 |
50 |
55.5 |
66.4 |
1015 |
|
Large seeded |
||||||||
BG 1073 X BG 1048 |
57.5 |
148 |
42 |
120 |
40.0** |
182.1** |
2840** |
13.6 |
BG 1073 X BG 1003 |
55.7 |
150* |
35 |
84 |
34.6* |
132.6 |
2230 |
|
Pusa 1053 Large Seeded Check |
59.2 |
144 |
47 |
125 |
32.5 |
160.7 |
2500 |
|
Medium large seeded |
||||||||
BG 1073 X BG 267 |
60.0** |
149 |
46** |
90 |
29.2** |
115.3 |
2050** |
27.3 |
BG 1073 X BGD 70 |
58.3** |
144 |
48** |
70 |
30.0** |
120.2 |
2080** |
29.2 |
Pusa 1003 Medium large seeded Check |
55.4 |
144 |
34 |
90 |
24.2 |
142.4 |
1610 |
|
LSD(P=0.05) |
1.639 |
5.478 |
1.361 |
2.299 |
1.754 |
5.077 |
68.991 |
|
LSD (P=0.01) |
2.213 |
7.398 |
1.838 |
3.104 |
2.369 |
6.856 |
93.165 |
|
CV (%) |
2.0 |
3.0 |
3.0 |
2.0 |
3.0 |
3.0 |
2.5 |
* ELS = Extra Large Seeded Types
In cross 1 (BG 1073 x BG1082) and cross 2 (BG 1073 x BG 1072), both parents were extra-large-seeded with good resistance against soil-borne diseases, high yield potential, medium maturity and excellent early vigor. Selection in each generation was focused on 100-seed weight in the segregating populations, simultaneously with early vigor, medium maturity, more number of branches, more number of pods and high biomass production,. Thus, segregants from crosses 1 and 2 were obtained that showed superior performance for different agronomic traits. Based on these findings it can be concluded that selection for large seed size and high seed yield traits can simultaneously be carried out The study of genotypic correlations showed that the interrelationship of seed yield with number of branches, number of pods and biomass production was highly significantly positive. When correlations were carried out without extra large seeded control lines, the correlations of seed yield with seed size were also high and positive. However, when the correlations were carried out including extra large seeded control lines the association between seed yield and seed size was non significant in negative direction, indicating that large seeded types are poor yielding under water limiting environments.
It can be concluded from the study that adaptation to drought prone environments can be successfully enhanced by genetic manipulation and careful selection while advancing through each generation.
This investigation showed that the poor adaptation of large-seeded kabuli genotypes of chickpea to drought-prone environments could be improved by breeding and selection. It was also concluded that agronomic traits, such as the number of branches, number of pods, total biomass production and medium-early maturity, played a crucial role in the adaptation of chickpeas to unfavorable environments. The selection strategies during generation advancement also played an important role in the identification of tolerant and adapted genotypes. This was possible due to the new recombinations of desirable genes that emerged during hybridization.
Yadav S.S., Turner N.C., Berger J., Kumar J., Hegde V.S., and Kumar S. (2003). Development of widely adapted kabuli cultivars. In Proceedings of International Chickpea Conference, 20-22 January 2003, Raipur, Chhatisgarh, India, pp 20-27.