Hubungan karakter morfologi dan fisiologi dengan hasil dan upaya meningkatkan hasil padi varietas unggul

Abstract

The objective of the research was to study relationship between morphological and physiological traits with yield and its components and the cultivation effort to increase grain yield of various types of rice cultivars. Experiment was conducted at Muara Experimental Station, Indonesian Center for Rice Research, Bogor, and at Babakan Experiment Station, University Farm IPB, Bogor, from June 2010 until November 2011. The study consisted of 4 experiments. The first experiment was conducted from June until December 2010 to study morphological characters and agronomy of various types of rice cultivars. The results showed that the top three leaves of new plant type (NPT) were better than those of local varieties (LV), improved new varieties (INV), and hybrid varieties. NPT and hybrids showed erect leaf characteristics and LV had droopy leaf characteristics. The sink capacity in NPT and hybrids was larger than that of INV and LV, but filled grains percentage in the NPT were lower than that of INV and LV. The highest yield was achieved by B11143 line (6.93 tons dry grain ready to mill/ha). The second experiment was conducted from December 2010 until May 2011. The objective of the research was to determine relationship between physiological characteristics with yield and its components in improved rice varieties. The results showed that physiological characteristics of NPT and hybrids were better than LV and INV. The physiological characters of NPT were high in photosynthetic rate, crop growth rate (CGR), and net assimilation rate (NAR) which was maintaned until seed filling stage. The highest yield was achieved by B11143 line (7.32 tons dry grain ready to mill /ha). The higher grain yield was caused by difference in physiological characteristics. The CGR, NAR, chlorophyll, and sugar content were correlated with yield components and yield. The third experiment was conducted from July until November 2011, to study plant spacing to increase yield of various types of rice cultivars. The result showed that yield was enhanced and the best was achieved by plant spacing of 15 cm x 30 cm in Ciherang, Maro, and B11143, while Pandan Wangi was not influenced by plant spacing. The fourth experiment was conducted from May until October 2011, to study nitrogen management to increase yield of various types of rice cultivars. The result showed that increase in nitrogen fertilization increased yield of all varieties. In the N management study, the highest yield was achieved by Ciherang, B11143 and Maro varieties at 125 kg N/ha, while Pandan Wangi at 100 kg N/ha. There was a positive correlation between yield and nitrogen absorbtion and content. Maro varieties at 125 N/ha showed higher absorption and agronomy efficiency (87.9% and 31 kg grain/kg N respectively).