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The whitefly, Bemisia tabaci (Gennadius) is a polyphagous pest causing considerable yield loss to many crops around the globe. It is a phloem feeder and transmits several viral diseases as well. It has great genetic diversity and is considered a complex of biotypes. Despite the adoption of several available control strategies, management by chemical pesticides has still been the first choice for the farmers to protect their crops. However, prolonged use of chemical pesticides has ultimately accelerated the development of multifold resistance against various groups of insecticides in different parts of the world. The status of development of insecticide resistance against different groups of insecticides by this pest, mechanisms of resistance, cross-resistance, role of detoxifying enzymes, and management issues have been discussed in this chapter.

A survey was conducted to study the incidence of infertility in crossbred cows and distribution of repeat breeding crossbred animals in Niali and Kantapara block of Cuttack district, Odisha, India which revealed that, the incidence of reproductive problems were 45.18 per cent in cross bred cows and 25.47 per cent in heifers. Out of the total reproductive disorders, 36.89, 51.94 and 11.17 per cent of cases were recorded as postpartum anoestrus, repeat breeding and miscellaneous disorders, respectively in crossbred cows. In crossbred heifers the incidence of anestrus, repeat breeding, delayed maturity and miscellaneous disorders were recorded to be 38.21, 45.53, 7.32 and 8.94 per cent respectively. Incidence of infertility was higher in summer months (45.29%) than that in rainy (25.23%) or winter (29.48%) season. Incidence of repeat breeding in cows included in the study recorded to be highest in second calvers (40.19%) followed by first (21.50%) and third calvers (13.08%). Incidence of repeat breeding was higher in cows with average daily milk yield of 10-12 litres and above. The cows with 6-8 litres of average daily milk yield recorded to be the lowest (9.35%). Incidence rate for repeat breeding in animals was recorded to be highest (43.56%) in cows with a body condition score of 1-2. The overall distribution of repeat breeding in animals was found to be 30 and 70 per cent with sub active and functional ovaries. However cows with non-functional ovary did not reveal any repeat breeding problems.

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