~ 617 ~ International Journal of Chemical Studies 2019; 7(5): 617-620 P-ISSN: 2349–8528 E-ISSN: 2321–4902 IJCS 2019; 7(5): 617-620 © 2019 IJCS Received: 16-07-2019 Accepted: 18-08-2019 Kiran BO Department of Crop Physiology University of Agricultural Sciences Dharwad, Karnataka, India Rajendra G Deshmukh Department of Crop Physiology University of Agricultural Sciences Dharwad, Karnataka, India Correspondence Kiran BO Department of Crop Physiology University of Agricultural Sciences Dharwad, Karnataka, India Correlation studies on effect of temperature regimes on traits associated with yield components in chickpea ( Cicer arietinum L.) genotypes Kiran BO and VP Chimmad Abstract High temperature is an important factor affecting chickpea growth, development and grain yield. Understanding the plant response to higher temperature is a key factor genotype selection for reproductive efficiency in chickpea. Under 48 th SMW date of sowing (D3) seed yield per plant recorded positive association with pod number per plant, pod weight per plant, total flower produced, total dry matter per plant, test weight and harvest index (0.854**, 0.993**, 0.404**, 0.780**, 0.414** and 0.617**, respectively). The degree of association for seed yield was higher in 48 th SMW compared to 41 st , 44 th and pooled dates of sowing. The total flower production and pod number decreased from D1 to D3 and this decrease was attributed to flower abortion due to higher temperature coincided with flowering period. Harvest index recorded positive association with pod number per plant, pod weight per plant and total flower produced (0.610**, 0.616** and 0.462**, respectively) under 48 th SMW. However, seed yield per plant was significantly and negatively associated with flower to pod ratio under 41 st , 44 th , 48 th , SMW and pooled date of sowing. Further, total flower count recorded positive association with flower to pod ratio, harvest index and seed yield (0.354**, 0.462** and 0.404**, respectively). This suggested that number of flower produced is not only dependent on total dry matter but also on maximum and minimum temperature. The experiment revealed that dates of sowing place an important role in determining dry matter accumulation and flower production in chickpea. Keywords: Pod number, harvest index, flower to pod ratio, total flower count and seed yield Introduction Chickpea is an important cool-season food legume, widely cultivated around the world, which experiences a range of high temperatures and is reported to be sensitive to heat stress particularly during day temperatures above 35 0 C during the reproductive stage are particularly detrimental and hence yield potential suffers. A 1 o C increase in seasonal temperature would decrease chickpea yield by 53 kg ha -1 (Kalra et al., 2008) [6] . Reproductive phase in chickpea is reported to be highly susceptible to heat stress (temperatures above 32/20 o C) as indicated by reduced flower production. Therefore, floral study is being considered as useful indicators for sensitivity of chickpea to temperature stress. The extent of damage to either male or female organs depends upon the stage of microsporogenesis or megasporogenesis (Wang et al., 2006) [6] . Heat stress post-anthesis in chickpea reduces seed number, seed weight and hence seed yield. Despite sever threat from increasing temperatures, considerable studies elucidating the high temperature effects on vegetative and reproductive phase using physiological assessment have been reported in chickpea. Exposure to heat stress (≥35 0 C) at flowering and podding in chickpea is known to result in drastic reductions in seed yields. However, heat stress has received relatively more attention in chickpea breeding programs for heat tolerant during recent years. Crop with delayed sowing, experiences higher temperature that coincides with the reproductive phase mainly flowering and pod development stage. The floral parts being sensitive to heat stress leads to lack of pollination, abscission of flower buds, reduced flower production and pods with substantial yield loss. Hot (> 30 ºC) and dry atmospheric conditions lead to profligate loss of flower buds and open flowers in chickpea (Krishnamurthy et al., 2011). High temperature after flower opening decreases chickpea seed yield by reducing the number of seeds per plant, dry matter accumulation and seed weight per seed.