การศึกษาชีววิทยาและการจัดการข้าวแดงในการผลิตพันธุ์ข้าวภาคใต้

Abstract

Red rice is a noxious weed in rice production. Since contamination of red pericarp grain in rice reduces the grade and price of the product. Biological study of red rice aimed at obtaining informations for management and elimination of this weed pest by collecting 91 samples of farmers'seeds in 3 provinces, they are 49 samples from Pattalung, 21 samples from Trang and 21 samples from Songkhla respectively. Those seeds had been analyzed for red rice as to know its severe infestation. Then red rice contaminant seeds were grown in pot to study the agricultural characteristics. The results revealed that rice seed samples from Pattalung province contaminated with red rice 47 samples or 95.92 percent, number of red rice seeds found were between 0-10,433 seeds. Rice seed samples from Trang province contaminated with red rice 10 samples or 47.62 percent, number of red rice seeds found were between 0-690 seeds and rice seed samples from Songkhla province contaminated with red rice 21 samples or 100 percent, number of red rice seeds found were between 1-3,125 seeds. It was found that the quality of 91 seed samples having genetic purity 94.10-97.81 percent, red rice 0-10,433 seeds, other rice seed varieties 1-135 seeds, inert matter 2.19-5.89 percent, germination percentage 90-98 percent. Brown rice with 5.39-7.40 mm. long and 1.80-2.46 mm. wide. Chemical quality of red rice was 16.72- 23.54 percent amylose content, gel consistency was 26-35 mm., alkali test was 4.6- 6.9, elongation ratio was 1.41-1.92. The color of paddy rice were straw color, brown and light purple.