Cytological Study On Anther Development Of Temian S-1 And The Effect Of Temperature On Cotton Pollen Germination And Tube Growth

Twelve materials, including cotton thermo-sensitive male sterile line, Temian S-1and high temperature tolerant lines, conventional cultivars, insect resistant lines andso on, were used as materials in present study. These materials were numbered fromone to twelve, and the No.12 is Temian S-1. The relationship between young budgrowth and the stage of pollen development, morphology and anther development ofTemian S-1, the effects of different temperatures on pollen germination and pollentube growth, the relationship among boll numbers, boll retention, maximum pollentube length (PTLmax) and maximum pollen germination (PGmax), and pollenmorphological of various materials under high temperatures were investingated in thepaper.(1)Anther development of Temian S-1 has five stages. The stages of pollendevelopment are related with the buds.growth. When the length of bud is 2mm～3mm,the microspore development is at stage of sporogenous cell multiplication; When thelength of bud is 3mm～3.5mm, the microspore development is at stage of pollenmother cells (PMCs)miosis; When the length of bud is 3.5mm～5mm, the microsporedevelopment is at stage of tetrad formation and sporules releasing; When the length ofbud is 5mm～8mm, the microspore development is at stage of pollen grains growth;When the length of bud is longer than 8mm, the pollen growth are mature.(2)The results of cytologyical research showed that there had no pollen grains inTemian S-1 anther or had few normal and many abnormal pollen grains above 30℃under field condition. At the stage of abortion, PMCs miosis appeared abnormal, suchas linked PMCs, multi spores, andabnormal spores.(3)The results of various temperature treatments showed: Temian S-1 had thehighest pollen germination percentage and the longest pollen tube length in in vitroculture at 25℃.For other materials, the pollen germination percentage was highest at30℃, and the pollen tube length was longest at 25℃. The PGmax ranged from57.67% for material 1 to 28.07% for Temian S-1; and the PTLmax varied770μm formaterial 5 to 350μm for Temian S-1. (4)In the field high temperature stress conditions, the boll number and bollretention were significant correlated with the pollen germination percentage andpollen tube length. In general, the cotton lines which have higher pollen germinationsand longer pollen tube, have higher boll retention and boll number, and the onesmaterials which have lower pollen germinations and shorter pollen tube, have lowerboll retention and boll number.(5) Because of difference effects of various temperature treatments on differencematerials, the effect of high temperature on pollen development of Temian S-1 isbiggest, and the percentage of morphologically abnormal pollen grains was more than50% and was four to eight times on cotton pistils of tolerant materials.