~ 1 ~ Journal of Pharmacognosy and Phytochemistry 2019; SP2: 01-03 E-ISSN: 2278-4136 P-ISSN: 2349-8234 JPP 2019; SP2: 01-03 Ambika Rajendran Scientist, Division of Genetics, ICAR-Indian Agricultural Research Institute, PUSA Campus, New Delhi, India Lal SK Principal Scientist, Division of Genetics, ICAR-Indian Agricultural Research Institute, PUSA Campus, New Delhi, India Jain SK Principal Scientist, Division of Seed Science and Technology, ICAR-Indian Agricultural Research Institute, PUSA Campus, New Delhi, India Dhandapani Raju ICAR-Indian Agricultural Research Institute, PUSA Campus, New Delhi, India Correspondence Ambika Rajendran Scientist, Division of Genetics, ICAR-Indian Agricultural Research Institute, PUSA Campus, New Delhi, India Screening of soybean genotypes for pre-germination anaerobic stress tolerance to waterlogging Ambika Rajendran, Lal SK, Jain SK and Dhandapani Raju Abstract Waterlogging is a common abiotic stress in kharif season (monsoon) dependent crops like soybean, the objective of this study was to evaluate the possibility of finding a morphological trait as selection criteria of soybean genotypes under waterlogging anaerobic stress. The experiment was carried out in the stage of germination. Percent germination was measured during water logging stress and stress recovery. Our results indicated the presence of genetic variability for germination. Percent germination associated with pre-germination under stress conditions can be used as selection criteria for waterlogging-tolerant soybean in breeding programs. Keywords: soybean, genotypes, stress tolerance, waterlogging Introduction Soybean is an important source of oil and protein worldwide. In Indian soybean is a kharif crop grown in an area of 109.72 lakhha with a productivity of 114lakhMT. Kharif season is characterized by unprecedented rainfall that leads to water logging in fields. Waterlogging is a serious abiotic problem in Soybean causing a loss of nearly 16 percent in productivity worldwide. Transient water logging is seen to affect seedling growth and further crop yield in several crops like soybean (Glycine max), pea (Pisumsativum), wheat, maize, and rice (Magneschi and Perata, 2009; Al-Aniet al., 1985) [6] . Flooding affects early stages of soybean during crop season (Griffin and Saxton, 1988) [4] . Waterlogging affects early 30-45 days covering emergence, cotyledon and vegetative 1,2,3,4 trifoliate leave stages. Tolerance of genotype to pre-germination covering one to fifteen days (sowing/seed stage to vegetative cotyledonary stage) can help soybean crop tolerate flooded situation. Injuries due to water logging are mainly due to lack of oxygen (Dennis et al., 2000) [3] . However, breeding for tolerance to water logging in early stages of soybean is limited. Screening based on the key traits and its responses can assist selection while screening large number of genotypes. Reduction in percent germination would be the most vulnerable response of pre-germination water logging. Earlier studies support the reduction in germination percentage and duration of emergence of soybean seed (McDonald et al., 1988; Wuebker et al., 2001) [9] . Such responses can differentiate tolerant and susceptible genotypes (Zaidi et al., 2012) [10] . The available genotypic variation could be exploited in developing soybean varieties that can tolerate pre- germination conditions of low oxygen during waterlogging.Suitable screening techniques, morpho-physiological traits associated with tolerance and identification of promising genotypes are the requirements of selection and development of waterlogging tolerant soybean.This study aimed to identify tolerantand susceptible genotypes at seedgermination stage based on percent germination and delay in emergence from a wide range of genotypes. Materials and Methods This experiment was conducted to evaluate germination of 128 soybean genotypes that included germplasm and trial entries in a range of waterlogging durations. Based on literatures, the waterlogging duration above 2 days water logging was sufficient to inhibit germination. Five durations (3, 5, 7, 9 and 11 days waterlogging) were therefore evaluatedas treatments along with a well-drained (control) condition in this experiment. Three replications of 100 seeds of each genotype were used in a completely randomized design (CRD-factorial).Seeds were surface-sterilized and placed to germinate in perforated plastic cups with peat-vermiculite mixture (1: 1). These perforated cups were kept in traysfilled with water and maintained in germination chamber that provided a temperature of 24 0 C. It is seen to maintain water level of 2cm above the soil level in each cup during the entire period of treatment. This arrangement is kept until treatment duration. After the water logging duration, the cups were