Critical Period of Weed Control in Winter Canola (Brassica napus L.) in a Semi-Arid Region
| Autor: | Saeed Reza Yaghoobi, Majid AghaAlikhani |
|---|---|
| Rok vydání: | 2008 |
| Předmět: |
Crops
Agricultural Agroecosystem Time Factors food.ingredient Gompertz function Brassica Growing season Iran Crop Soil food Species Specificity Canola Ecosystem biology Brassica napus Agriculture Weed control biology.organism_classification Plant Leaves Agronomy Regression Analysis Seasons Desert Climate Weed Agronomy and Crop Science |
| Zdroj: | Pakistan Journal of Biological Sciences. 11:773-777 |
| ISSN: | 1028-8880 |
| DOI: | 10.3923/pjbs.2008.773.777 |
| Popis: | In order to determine the critical period of weed control in winter canola (Brassica napus L. cv. Okapi) an experiment was carried out at research field of Tarbiat Modarres University, Tehran, Iran on 2004-2005 growing season. Fourteen experimental treatments which divided into two sets were arranged in Randomized complete blocks design with four replications. In the first set, the crop was kept weed-free from emergence time to two-leaf stage (V2), four-leaf stage (V4), six-leaf stage (V6), eight-leaf stage (V8), early flowering (IF), 50% of silique set (50% SS) and final harvest (H). In the second set, weeds where permitted to grow with the crop until above mentioned stages. In this study critical period of weed control was determined according to evaluate seed bank emerged weed biomass effect on canola grain yield loss using Gompertz and logistic equations. Result showed a critical time of weed control about 25 days after emergence (between four to six-leaf stages) with 5% accepted yield loss. Therefore, weed control in this time could provide the best result and avoid yield loss and damage to agroecosystem. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|