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In-situ field studies were conducted for three consecutive baby corn (Zea mays L.) growing seasons to quantify the amount of reactive N flowing beyond the rhizosphere while defining mitigation strategies. The N applications based on plant need were agronomically more efficient than the fixed-time blanket N applications. Average area-scaled leachate N losses in the winter season were 24 and 8% higher than the summer and spring seasons, respectively. A smaller root system at low N rate likely restricts plant N uptake and accelerates the magnitude of N leaching factor ranging from 6 to 9% in different seasons. Leachate N-flux peaks were more pronounced at early growth stages, attributed to the N supply in excess of the plant need. Residual soil mineral N varied little despite a wide range of fertilizer N rates, hence there was no evidence to support the idea that soils should be replenished for N removal by crops at fixed growth stages. Rather, N losses to the environment were greater using fixed-timing blanket N applications, which can be mitigated by a shift to N fertilization based on assessment of plant need. Use of the PAU-leaf colour chart and chlorophyll meter to guide need-based fertilizer N topdressings reduced average leachate NO3¯-N load by 69% over blanket N use practice, while producing an average 17% higher cob yield in baby corn. Hence, the blanket N use practices should be replaced with need-based N management strategies to mitigate environmental footprints of N use in the baby corn based cropping system.

A chickpea collection of 1600 desi and 1400 kabuli were evaluated for yield losses arising from pod borer (Helicoverpa armigera) infestation under rainfed conditions by spraying half the plots to prevent pod borer infestation and allowing the other half to be infested. From these lines, 82 were selected for further detailed evaluation of Helicoverpa resistance and drought resistance under irrigated and rainfed conditions. The yield losses from Helicoverpa damage varied from 10 to 33% depending on the chickpea type and the growing environment. Spreading types were more susceptible to Helicoverpa damage than erect types, as were kabuli types compared to desi types. Yield losses due to Helicoverpa infestation were always greater in the irrigated than in the rainfed materials. Terminal drought reduced yields by 13–37% depending on plant type. The yields in the kabuli c“hickpea lines were more severely reduced than were the desi types, due to a greater reduction in the number of branches and pods per plant in the kabuli compared to the desi lines. It appears that the extent of pod borer damage varies between the chickpea types, and that desi types have greater drought resistance than kabuli ones. These characteristics should be informative for the population improvement of chickpea for environments in which terminal drought and Helicoverpa damage occur frequently.

In order to investigate specific and general adaptation of chickpea in India, a wide range of sub-continental, Australian and Mediterranean genotypes were grown across seven sites characterizing the major chickpea growing areas over 3 years, and extensive data on plant stand, early vigour, phenology, productivity and yield components collected. High and low yielding sites were clearly separated by a range of physical and biological characters, low yield being associated with low latitude and pre-season rainfall, high temperature, early phenology, short crop duration, low biomass and fecundity. Genotype by environment interactions for yield were highly significant (P

Chickpea (Cicer arietinum L.) is the third most important pulse crop in the world and India is the largest producer of this crop. Nevertheless, its yield in India is low (0.7 tone per hectare (t/ha)) as compared to Australia, Egypt, Israel and Italy (1 t/ha) (FAOSTAT 2008, http://faostat.fao.org/). There has been a significant change in the scenario of chickpea cultivation in India during the past three decades. The expansion of irrigated agriculture in northern India has led to displacement of chickpea with wheat in large area. As a result, the area under chickpea reduced from 3.2 million ha to 1.0 million ha in northern and northwestern India (Punjab, Haryana and Uttar Pradesh), while it increased from 2.6 million ha to 4.3 million ha in central and southern India (Madhya Pradesh, Maharashtra, Andhra Pradesh and Karnataka) from 1985 to 1990. Because of relatively warm environments in central and southern India, the crop is challenged by Fusarium wilt, a major yield reducing disease, while in northwestern India, due to cooler environments, the crop is exposed to a severe foliar disease Ascochyta blight. The narrow genetic base among cultivated chickpea accessions is limiting genetic improvement of chickpea through breeding efforts. Understanding the extent of natural variation among cultivated chickpea and wild accessions at molecular level is essential to develop prebreeding and breeding strategies for chickpea. Until recently, the low intraspecific and inter-specific polymorphism in chickpea accessions detected by molecular markers and the scarcity of codominant DNA-based markers were serious constraints that hindered the preparation of dense molecular genetic maps or tagging of important traits in chickpea. However, recent studies using STMS markers reveal fairly high levels of