A major gene for the number of days from sowing to appearance of the first flower (time of flowering) was identified in a cross between an extrashort duration chickpea (Cicer arietinum L.) variety, ICCV 2, and a medium duration variety, JG 62. The F2 population was advanced through the single-seed-descent method to develop random recombinant inbred lines (RILs). Time of flowering was recorded for the parents and 66 F(6) RILs from this cross that were grown in a Vertisol field in the post-rainy season of 1996-1997. Similarly the parents, F(1) and F(10) RILs were evaluated in 1997-1998. The F(1) flowered along with JG 62. The time of flowering for the two sets of RILs showed bimodal distributions with nearly equal peaks. One peak corresponded with ICCV 2 and the other with JG 62. This suggests that a single gene controls the difference for the time of flowering between ICCV 2 and JG 62 and the allele carried by the latter parent is dominant. To our knowledge no gene has been identified for the time of flowering in chickpea. Therefore the allele carried by JG 62 is designated as Efl-1 and that by ICCV 2 as efl-1. The proposed genotype for ICCV 2 is efl-1 efl-1 and for JG 62 is Efl-1 Efl-1. The genotype efl-1 efl-1 reduces the time of flowering at ICRISAT by nearly 3 weeks. The significance of this gene for breeding for early maturity and genome mapping has been discussed.

Compared with mono-cultures, beans grown in association with maize showed generally less incidence of the following diseases and pests: halo blight, bean common mosaic, anthracnose, common blight, scab, Phoma, mildew, bolworm and to a lesser extent angular leaf spot. For white mold and the black beetle Systates the opposite was observed. Rust and aphids were erratic in this respect.Apparently a kind of cultural control of the major bean diseases in Kenya is effected by growing beans in association with maize.

SummaryThe character of determinate plant growth has not been reported for chickpea and has not been observed in the world germplasm collection at ICRISAT, Patancheru, India. A determinate growth habit would be desirable where growing conditions often lead to excessive vegetative growth . We attempted to generate this trait by mutation breeding . Seeds of the cultivar ICCV 6 were exposed to varying irradiation treatments, Ml and M2 populations were raised, and in the latter one plant was detected that showed the determinate growth habit and female sterility . The character of determinate growth segregated in a postulated digenic epistatic 3 :13 fashion in the F2 and confirmed its digenic mode of inheritance in the F3 and F4 . The symbol cd is proposed for the allele conditioning for determinancy and Dt for the allele expressing the determinate trait . Continued mutation breeding with this and other material may result in identifying fully fertile, determinate plant types .

Screening for Ascochyta blight resistance In chlckpea under controlled environment and field cond~tions Plant I11r. 79:122-135. The occurrence and severity of Ascochyta blight of chickpea 1s influenced by env~ronrnenlal Pactors, which can complicate field screening. A control;ed-env~ronrnent plant growth room was developed at ICRISAT Asia Center to rapidly screen ch~ckpea genotypes within 15 day, for resistance to Ascochyta blight caused by Ascochyra rahret. A posltlve correlation was obcerved between results from controlled-environment and field screenings In an area where the pathogen is endemic. Ascochyta blight, a fungal disease of chickpea (Cicer arierinum L.) caused by Ascochyra rabiei (Pass.) Lab., can devastate chickpea crops over large areas if weather conditions favor infection and spread of the pathogen. The years 1979-80 and 1981-82, for instance, were disastrous for chickpea production in

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