Effect of nursery seeding date and phosphorus fertilization on rice seedling growth

Abstract

During rabi (Nov-Dec), the growth of rice seedlings in nurseries in some of the rice-growing areas in Andhra Pradesh, India, is poor due to the prevailing low temperature. The suppressed growth of seedlings caused by low temperature is described as cold injury (Shibata 1970). Also, absorption of phosphorus was most strongly inhibited at low temperature (<16 ° C). The low concentration of P in soil solution P (2.5 times less) during cooler months necessitates the application of higher doses of P (Katyal and Venkatramaya 1983). Hence, there exists a need for producing vigorous seedlings through proper nursery management. A field study was conducted during the 2001-02 rabi season at College Farm, Rajendranagar, to evaluate the effect of low temperature and P fertilization on seedling growth of rice variety IR64. The treatments consisted of three dates of wet nursery sowing (20 Nov, 1 Dec, and 10 Dec) and four levels of P fertilization (0.5, 1.0, and 2.0 kg P 2 O 5 100 m –2 ). Soil was a sandy clay loam with pH 7.9, low in available N (223 kg ha –1 ), and medium in P (17 kg ha –1 ) and K (242 kg ha –1 ). The experiment was laid out in a randomized complete block design (factorial) with three replications. Each nursery plot was 2 m × 3 m and was fertilized with a uniform dose of N and K at 1.0 kg 100 m –2.