The rice weevil, Sitophilus oryzae (Linnaeus) is a major pest of rice at storage condition in Nep... more The rice weevil, Sitophilus oryzae (Linnaeus) is a major pest of rice at storage condition in Nepal. A lab experiment was conducted for varietal screening of rice genotypes against S. oryzae at the National Rice Research Program, Hardinath, Dhanusha, Nepal in 2020. The study was carried out in Completely Randomized Design (CRD) in a three replicates. Fifty gram of each seven popular rice genotypes i.e Sambha Mansuli Sub-1, Ramdhan, Radha-11, Bahuguni-1, Bahuguni-2, Hardinath-2 and Lalka Basmati were used to screen the potential weevil resistant rice cultivars. Ten pairs of newly emerged adult S. oryzae of uniform age obtained from stock culture were released in each plastic jar in no-choice tests, while twenty five pairs of S. oryzae were released in the center, in choice tests. Results were evaluated based on the grain damage percent, weight loss percent, and total live weevil population for 90 days from the date of experiment. The result demonstrated that Lalka Basmati was the lea...
The rice weevil, Sitophilus oryzae (Linnaeus) is a major pest of rice at storage condition in Nep... more The rice weevil, Sitophilus oryzae (Linnaeus) is a major pest of rice at storage condition in Nepal. A lab experiment was conducted for varietal screening of rice genotypes against S. oryzae at the National Rice Research Program, Hardinath, Dhanusha, Nepal in 2020. The study was carried out in Completely Randomized Design (CRD) in a three replicates. Fifty gram of each seven popular rice genotypes i.e Sambha Mansuli Sub-1, Ramdhan, Radha-11, Bahuguni-1, Bahuguni-2, Hardinath-2 and Lalka Basmati were used to screen the potential weevil resistant rice cultivars. Ten pairs of newly emerged adult S. oryzae of uniform age obtained from stock culture were released in each plastic jar in no-choice tests, while twenty five pairs of S. oryzae were released in the center, in choice tests. Results were evaluated based on the grain damage percent, weight loss percent, and total live weevil population for 90 days from the date of experiment. The result demonstrated that Lalka Basmati was the least damaged rice cultivar followed by Bahuguni-2. The highest weevil population over 90 days was recorded in Sambha Mansuli Sub-1 followed by Hardinath-2 and the least weevil population was found on Lalka Basmati followed by Bahuguni -2 in both test conditions. Lowest to highest damage ranking of rice genotypes was: Lalka Basmati<Bahuguni-2<Bahuguni-1<Radha-11<Ramdhan<Hardinath-2<Sambha Mansuli Sub-1. Thus, promotion of Lalka Basmati & Bahuguni-2 varieties is recommended to reduce the infestation of rice weevil in the storehouse condition. This information is useful for host plant resistant breeding program for the plant breeder.
An experiment was conducted to evaluate the efficacy of plant-based repellent powders for S. oryz... more An experiment was conducted to evaluate the efficacy of plant-based repellent powders for S. oryzae at the National Rice Research Program, Hardinath, Dhanusha, Nepal in 2020 at laboratory condition. Two hundred gram of paddy grains of cv. Sambha Mansuli Sub-1 was kept in each plastic jar in the experiment. Ten pairs of newly emerged adult rice weevil, S. oryzae of uniform age obtained from stock culture were released in each plastic jar. Laboratory bioassay contained Acorus calamus (rhizome powder) @10 gm/kg, Piper nigrum (seed powder) @10 gm/kg, Curcuma longa (rhizome powder) @10 gm/kg, Azadirachta indica (kernel powder) @ 10gm/kg, Zingiber officinale (rhizome powder) @10 gm/kg, and Malathion powder 5% dust @2 gm/kg were used for the rice weevil. Acorus calamus was the most effective botanical powder followed by P. nigrum to reduce grain damage percent on number basis (1.15%) and on weight basis (1.22%), weight loss percent (0.84%) & weevil population count (1.54). The efficacy ranks of the botanicals were: A. calamus>P. nigrum>A. indica>Z. officinale>C. longa. Thus, use of A. calamus powder is recommended to manage rice weevil in the storehouse condition.
The bio-efficacy of five plant leaf extracts were tested in Morang-2 variety of Rapeseed against ... more The bio-efficacy of five plant leaf extracts were tested in Morang-2 variety of Rapeseed against Mustard aphid (Lipaphis erysimi Kalt.) during November to March, 2016/17 at research field of Institute of Agriculture and Animal Science (IAAS), Lamjung Campus, Lamjung, Nepal. The plant leaf extracts were prepared by decomposing chopped leaves of Neem, Bakaino, Hattibar, Khirro, and Bojho in cow urine for one month period. Total five extracts were prepared, one by mixing all the leaf while remaining four extracts were prepared excluding one ingredient in each mixture but keeping Tobacco and Bojho in all five extracts. The experiment was laid out in Randomized Completely Block Design using five botanical extracts, chemical (Cypermethrin 10% EC) and control which were replicated thrice. The Rapeseed plant was sprayed with prepared extracts at 30 days after sowing (DAS), 45 DAS and 60 DAS and aphid number counted after 5, 10 and 15 days of each spray from 10 cm apical shoot. The greatest ...
The rice weevil, Sitophilus oryzae (Linnaeus) is a major pest of rice at storage condition in Nep... more The rice weevil, Sitophilus oryzae (Linnaeus) is a major pest of rice at storage condition in Nepal. A lab experiment was conducted for varietal screening of rice genotypes against S. oryzae at the National Rice Research Program, Hardinath, Dhanusha, Nepal in 2020. The study was carried out in Completely Randomized Design (CRD) in a three replicates. Fifty gram of each seven popular rice genotypes i.e Sambha Mansuli Sub-1, Ramdhan, Radha-11, Bahuguni-1, Bahuguni-2, Hardinath-2 and Lalka Basmati were used to screen the potential weevil resistant rice cultivars. Ten pairs of newly emerged adult S. oryzae of uniform age obtained from stock culture were released in each plastic jar in no-choice tests, while twenty five pairs of S. oryzae were released in the center, in choice tests. Results were evaluated based on the grain damage percent, weight loss percent, and total live weevil population for 90 days from the date of experiment. The result demonstrated that Lalka Basmati was the lea...
The rice weevil, Sitophilus oryzae (Linnaeus) is a major pest of rice at storage condition in Nep... more The rice weevil, Sitophilus oryzae (Linnaeus) is a major pest of rice at storage condition in Nepal. A lab experiment was conducted for varietal screening of rice genotypes against S. oryzae at the National Rice Research Program, Hardinath, Dhanusha, Nepal in 2020. The study was carried out in Completely Randomized Design (CRD) in a three replicates. Fifty gram of each seven popular rice genotypes i.e Sambha Mansuli Sub-1, Ramdhan, Radha-11, Bahuguni-1, Bahuguni-2, Hardinath-2 and Lalka Basmati were used to screen the potential weevil resistant rice cultivars. Ten pairs of newly emerged adult S. oryzae of uniform age obtained from stock culture were released in each plastic jar in no-choice tests, while twenty five pairs of S. oryzae were released in the center, in choice tests. Results were evaluated based on the grain damage percent, weight loss percent, and total live weevil population for 90 days from the date of experiment. The result demonstrated that Lalka Basmati was the least damaged rice cultivar followed by Bahuguni-2. The highest weevil population over 90 days was recorded in Sambha Mansuli Sub-1 followed by Hardinath-2 and the least weevil population was found on Lalka Basmati followed by Bahuguni -2 in both test conditions. Lowest to highest damage ranking of rice genotypes was: Lalka Basmati<Bahuguni-2<Bahuguni-1<Radha-11<Ramdhan<Hardinath-2<Sambha Mansuli Sub-1. Thus, promotion of Lalka Basmati & Bahuguni-2 varieties is recommended to reduce the infestation of rice weevil in the storehouse condition. This information is useful for host plant resistant breeding program for the plant breeder.
An experiment was conducted to evaluate the efficacy of plant-based repellent powders for S. oryz... more An experiment was conducted to evaluate the efficacy of plant-based repellent powders for S. oryzae at the National Rice Research Program, Hardinath, Dhanusha, Nepal in 2020 at laboratory condition. Two hundred gram of paddy grains of cv. Sambha Mansuli Sub-1 was kept in each plastic jar in the experiment. Ten pairs of newly emerged adult rice weevil, S. oryzae of uniform age obtained from stock culture were released in each plastic jar. Laboratory bioassay contained Acorus calamus (rhizome powder) @10 gm/kg, Piper nigrum (seed powder) @10 gm/kg, Curcuma longa (rhizome powder) @10 gm/kg, Azadirachta indica (kernel powder) @ 10gm/kg, Zingiber officinale (rhizome powder) @10 gm/kg, and Malathion powder 5% dust @2 gm/kg were used for the rice weevil. Acorus calamus was the most effective botanical powder followed by P. nigrum to reduce grain damage percent on number basis (1.15%) and on weight basis (1.22%), weight loss percent (0.84%) & weevil population count (1.54). The efficacy ranks of the botanicals were: A. calamus>P. nigrum>A. indica>Z. officinale>C. longa. Thus, use of A. calamus powder is recommended to manage rice weevil in the storehouse condition.
The bio-efficacy of five plant leaf extracts were tested in Morang-2 variety of Rapeseed against ... more The bio-efficacy of five plant leaf extracts were tested in Morang-2 variety of Rapeseed against Mustard aphid (Lipaphis erysimi Kalt.) during November to March, 2016/17 at research field of Institute of Agriculture and Animal Science (IAAS), Lamjung Campus, Lamjung, Nepal. The plant leaf extracts were prepared by decomposing chopped leaves of Neem, Bakaino, Hattibar, Khirro, and Bojho in cow urine for one month period. Total five extracts were prepared, one by mixing all the leaf while remaining four extracts were prepared excluding one ingredient in each mixture but keeping Tobacco and Bojho in all five extracts. The experiment was laid out in Randomized Completely Block Design using five botanical extracts, chemical (Cypermethrin 10% EC) and control which were replicated thrice. The Rapeseed plant was sprayed with prepared extracts at 30 days after sowing (DAS), 45 DAS and 60 DAS and aphid number counted after 5, 10 and 15 days of each spray from 10 cm apical shoot. The greatest ...
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