Phenotypic Response of Rice Genotypes Under Submergence Conditions at Seedling Stage

Screening of twenty rice varieties with sub1 gene was performed to check their resistance under submergence conditions. This experiment involved growing of rice germ plasms sown in small pots filled with Irish Peat Moss. These pots were placed in incubator for germination. After ten days these pots were submerged in water tank to check their submergence resistance. Three varieties showed good tolerance against submergence as they grew less in length and seventeen varieties gave poor result as they grew more in length. Curr Inves Agri Curr Res Copyrights@ Mubashar Hussain, et al. Citation: Mubashar H, Umar N, Muhammad B, Nauman L. Phenotypic Response of Rice Genotypes Under Submergence Conditions at Seedling Stage. Curr Inves Agri Curr Res 5(4)2018. CIACR.MS.ID.000220. DOI: 10.32474/CIACR.2018. 05.000220. 723 induced increase in growth as a result food reserves of plant are protected, and It does not lodge when water level comes down [11,12]. Material and Methods 24 genotypes of rice were selected for submergence screening at seedling stage at Rice Research Institute, Kala Shah Kaku. Their soaking was done in normal water at room temperature for 24 hours. To start germination of seeds, they were placed in 24 petri dishes [13-15]. Medium used for growth was wetted filter paper and were placed in incubator at 35 degree centigrade and relative humidity 14.25% for 2 days. It was followed by sowing of germinated seed in plastic pots filled with Irish peat moss and these plastic pots were placed in growth chamber for 2 weeks at 26 degree centigrade with photoperiod of 12 hours. Process included soaking of first 24 genotypes (Figure 1). After 24 hours of soaking they were placed in incubator for incubation and after the development of roots and shoots in incubator they were sown in plastic pots filled with Irish peat moss and were placed in growth chamber where their temperature and humidity was maintained, and they were also kept in sunlight at day time to fulfill their light requirement. Irrigation and fertigation was applied at regular interval according to the requirements of plants. After 14 days half genotypes were shifted to submergence tank with half as their control [16-18]. The ph. of water filled in tank was 6.7. Length of plants was measured before shifting to submergence tank and It was also measured after 2 days, 4 days and one week along with control plants. Arrangement of pots was in completely randomized design (Figure 2). To check tolerance of plants against water submergence they were placed in submergence tank for seven days. Survival of plants was observed after seven days of submergence (Figure 3). Height of plants was noted before and after submergence and also during the time of submergence with interval of two days (Table 1). Figure 1: 1st two genotypes cannot survive due to harsh environmental conditions and become dead and same in case of genotype no 20. While from others genotype no 14 shows less difference which is 0.35 and it is best performer in this experiment and genotype no 6, 12 and 21 are at 2nd position and 21 genotypes is check variety, so they are also good performer but showing more difference then genotype 14. While genotype 15, 7, 8, 16, 19 are bad performer because they show great differences in plant height and when de submergence occurs, they will lodge down and cause decrease in yield. Curr Inves Agri Curr Res Copyrights@ Mubashar Hussain, et al. Citation: Mubashar H, Umar N, Muhammad B, Nauman L. Phenotypic Response of Rice Genotypes Under Submergence Conditions at Seedling Stage. Curr Inves Agri Curr Res 5(4)2018. CIACR.MS.ID.000220. DOI: 10.32474/CIACR.2018. 05.000220. 724 Figure 2: In case of control, genotype 11 and 12 cannot survive due to harsh environment conditions and become dead. Genotypes 15,16,17,18,20 and 25 shows 0.35 increase in length within a week while 14 genotypes get maximum height and genotype 13, 19 and 22 are in between performers of maximum and minimum. Figure 3: When we compare both cases of submergence as well as control, we get following results. In case of control, 11 and 12 genotypes are dead while in case of submergence 20th genotype is dead, so we cannot compare these genotypes. From others, 14th genotype gain more height in case of control comparing with submergence and other genotypes gain more height in case of submergence comparing with control. 12th and 14th genotypes are showing less height in submergence so they are good performers. While 17th and 25th genotypes can be used as submergence tolerance while genotypes 11th, 13th, 15th, 16th, 18th, 19th cannot be used as submergence tolerance due to more height.