Orobanche Species distribution and severity of infested areas in south and north Wollo zones of Amhara region, Ethiopia
Broomrapes (Orobanche species) are obligate holoparasitic flowering plant. Orobanche species are root parasite which can damage the crops underground before the weed emerged. Complete faba bean yield loss by this weed forced farmers to replace faba bean by cereal crops. The distribution of the weed is increasing annually. To obtain relevant information on the introduction and distribution of the weed, survey was conducted on randomly selected 72 farmers’ fields in 12 woredas in two zones, south and north Wollo. Four woredas, Kutaber, Dessie-zuria, Tenta and Mekidela are out of legumes production in south Wollo. In this survey, information was also gathered regarding farmers attitude and local control practices. Farmers practice is hand weeding but Orobanche shoots were emerged again in doubling and tripling. We cannot stop the dissemination of the weed due to the nature of dispersed agents such as wind, flood, farm machinery, crop seeds, animals, humans etc and the undulating features of the areas are all favorable agents to disperse the minute seeds of the parasitic weed and are beyond our capacity to control them, but we may bring a solution by multi-sector approach through developing resistant varieties using molecular breeding and with chemical control measures.
Different statistical methods to collect information about the adverse effects of climatic factors on cotton production
This study investigates the statistical relationship between various climatic factors and overall flower and boll production. Also, predicting effects of climatic factors during different convenient intervals (in days) on cotton flower and boll production compared with daily observations. Further, collects information about the nature of the relationship between various climatic factors and cotton boll development and the 15-day period both prior to and after initiation of individual bolls. And, provide information on the effect of various climatic factors and soil moisture status during the development stage on flower and boll production in cotton. Evaporation, sunshine duration, relative humidity, surface soil temperature at 1800 h, and maximum air temperature, are the important climatic factors that significantly affect flower and boll production. The five-day interval was found to be more adequately and sensibly related to yield parameters. Evaporation; minimum humidity and sunshine duration were the most effective climatic factors during preceding and succeeding periods on boll production and retention. There was a negative correlation between flower and boll production and either evaporation or sunshine duration, while that correlation with minimum relative humidity was positive.