dry matter remobilization, grain filling rate and duration has principle role on rice grain yield, and environment condition directly affect on them. for study the influence of climate factors a factorial field experiment in randomized complete blocks design with three replications conducted at haraz extention and technology development centre in spring 2013. treatments included rice cultivars ...

We investigated the presence of endophytic rhizobia within the roots of the wetland wild rice Oryza breviligulata, which is the ancestor of the African cultivated rice Oryza glaberrima. This primitive rice species grows in the same wetland sites as Aeschynomene sensitiva, an aquatic stem-nodulated legume associated with photosynthetic strains of Bradyrhizobium. Twenty endophytic and aquatic iso...

The present study aims to determine spectral bands that are best suited for characterizing rice agronomic variables. The data for this study came from ground-level hyperspectral reflectance measurements of rice at different stage. Reflectance was measured in discrete narrow bands between 350 and 2500 nm. Observed rice agronomic variables included leaf area index (LAI), wet biomass (WBM includin...

abstract sclerogenic fungal pathogens, are among the most important diseases of rice plant. sheath blight caused by rhizoctonia solani is one of the economically important diseases that attack a wide range of hosts. stem rot (magnaporthe salvinii) has also been found with different severity in most fields of guilan province. to determine sclerogenic fungal pathogens of rice plant, 141 isolates ...

The striped stem borer, Chilo suppressalis (Walker) (Lepidoptera: Pyralidae), is the most abundant stem borer of rice Oryza sativa L. (Poaceae) in temperate Asia. Chilo suppressalis also occurs throughout the tropical rice-growing areas of Asia, where it is generally second in abundance to the yellow stem borer, Scirpophaga incertulas (Walker) (Lepidoptera: Pyralidae) (Pathak & Khan, 1994). Ste...

Silicon soil amendment has been shown to enhance plant defenses against insect pests. Rice is a silicon-accumulating graminaceous plant. In the southern United States, the rice water weevil and stem borers are important pests of rice. Current management tactics for these pests rely heavily on the use of insecticides. This study evaluated the effects of silicon amendment when combined with curre...

Nitrogen-fixing activity associated with different wetland rice varieties was measured at various growth stages by an in situ acetylene reduction method after the activities of blue-green algae (cyanobacteria) in the flood water and on the lower portion of the rice stem were eliminated. Nitrogen-fixing activities associated with rice varieties differed with plant growth stages. The activities i...