Growth, Yield and Yield Components of American Cotton (Gossypium hirsutum L.) As Affected by Cultivars and Nitrogen Fertilizer
Nitrogen stress in upland cotton addresses significant and visible shortfalls in plant growth. It is an important element both in nature and agricultural conditions, for cotton plant growth and development. To evaluate the response of different yield and yield component of high yielding upland cotton cultivars to various split applications of nitrogen fertilizer, a two season field research was conducted during 2007 and 2008. Different experimental treatments were comprised on cotton leaf curl virus (CLCV) resistant high yielding cotton cultivars i.e. CIM-496, CIM-506, CIM-534 along with different nitrogen rate of Zero, 60, 110 and 160 kg ha -1 . However, cultivar CIM-534 produced significantly the highest plants, nodes per plant and flowering buds plant -1 . While, CIM-496 showed better potential in relation to leaf area index, crop growth rate, relative growth rate and net assimilation rate (physiological), dry biomass and number of bolls m -2 (reproductive) and seed cotton, cotton seed (yield) parameters during both the seasons. On increasing N rates, vegetative characteristics of cotton like plant height, nodes plant -1 and number of flowering buds per plant significantly gave better response with each cultivar. Advanced cotton cultivars produced significantly higher total dry biomass (TDM), bolls m -2 , seed cotton, cotton seed and GOT % age on each increment in applied nitrogen. The nitrogen fertilizer rate i.e. 160 kg ha -1 proved to be the optimum for the highest cotton yield and yield components. Further fibre characteristics such as staple length, uniformity ratio and maturity ratio significantly influenced by different cultivars.
Potassium and aldicarb-disulfoton effects on Verticillium wilt, yield, and quality of cotton
Optimum cotton (Gossypium hirsutum L.) yield with good fiver quality requires healthy vigorous plants throughout the season. Recently, verticillium wilt (Verticillium dahliae Kleb.) and K deficiency symptoms occurred during August and September in cotton grown on sandy loam soils of the Mississippi Delta. Symptoms developed earlier and faster in some cultivars compared with others. In a field study, applications of K and pesticides on verticillium wilt-K deficiency symptoms, yield and fiber quality of «DES 119» and «Stoneville 825» cottons were evaluated
Detection and Counting of On-Tree Citrus Fruit for Crop Yield Estimation
In this paper, we present a technique to estimate citrus fruit yield from the tree images. Manually counting the fruit for yield estimation for marketing and other managerial tasks is time consuming and requires human resources, which do not always come cheap. Different approaches have been used for the said purpose, yet separation of fruit from its background poses challenges, and renders the exercise inaccurate. In this paper, we use k-means segmentation for recognition of fruit, which segments the image accurately thus enabling more accurate yield estimation. We created a dataset containing 83 tree images with 4001 citrus fruits from three different fields. We are able to detect the on-tree fruits with an accuracy of 91.3%. In addition, we find a strong correlation between the manual and the automated fruit count by getting coefficients of determination R2 up to 0.99.