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The cotton mealybug, Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae), is an invasive pest of cotton, apart from several other important crops, and poses a serious threat to agricultural economy all over the world. Studies on the biology and population growth parameters of P. solenopsis on the five most preferred host plants, namely cotton (Gossypium hirsutum L.) (Malvaceae), China rose (Hibiscus rosa-sinensis L.) (Malvaceae), tomato (Lycopersicon esculentum Mill.) (Solanaceae), congress grass (Parthenium hysterophorus L.) (Asteraceae) and okra (Abelmoschus esculentus (L.) Moench) (Malvaceae) were undertaken in the laboratory under controlled temperature and relative humidity. The mean cumulative development time of females was 16.61 days on cotton, 14.16 days on China rose, 14.13 days on okra, 14.00 days on tomato and 13.57 days on congress grass. The longest oviposition period was recorded on cotton (15.20 ± 1.87 days), while it was in the range of 9-10 days in the remaining host plants. Females lived longer (27.40 ± 1.76 days) when reared on cotton, while their life was shortest on tomato (14.60 ± 0.96 days). The highest fecundity was observed on cotton (328.30 ± 23.42), whereas it was found to be in the range 178-212 on the other hosts. The survival frequency from crawler to adult in females was highest on cotton (27.53%), while it was the lowest on tomato (15.87%). The highest net reproductive rate (284.3 females/female/generation), mean length of a generation (31.24 days), and intrinsic rate of increase (0.19 day−1) were recorded on cotton. The finite rate of increase was in the range of 1.18-1.20 (females/female/day) for all the selected host plants. The weekly multiplication rate was highest on China rose and congress grass (3.78), while it was the least on tomato (3.28). The corrected generation time was dissimilar in all the selected host plants, being highest on cotton (31.39 days) and the least on congress grass (27.71 days). The doubling time was shortest on congress grass (3.61 days), while it was longest on tomato (4.11 days). Hence, the host plant species significantly affects population growth of P. solenopsis. [ABSTRACT FROM AUTHOR]

survey was conducted in 47 locations in nine cotton-growing states of India to identify the composition of mealybug species occurring on cotton. Results of the taxonomic study showed that two mealybug species, the solenopsis mealybug, Phenacoccus solenopsis (Tinsley), and the pink hibiscus mealybug, Maconellicoccus hirsutus (Green), were found to infest cotton plants from all nine cotton growing states of the country. However, P. solenopsis was found to be the predominant mealybug species, comprising 95% of the samples examined. P. solenopsis, which was hitherto not reported to occur in India, now appears to be widespread on cotton in almost all cotton-growing states of the country. P. solenopsis is an exotic species originated from the USA and was reported to damage cotton and crops of 14 families. This report discusses the implications of the introduction of this exotic polyphagous pest species and the necessary steps to mitigate its potential threat to agriculture in India. [ABSTRACT FROM AUTHOR]