Himachal Journal of Agricultural Research

Namburi Mounica Chowdary ¹, P. C. Sharma ¹

Affiliations
1 Department of Entomology, CSK Himachal Pradesh Krishi Vishvavidyalaya, Palampur - 176062, IN

Abstract

The bioefficacy of newer insecticides against diamondback moth, Plutella xylostella (L.) on cabbage was determined. Among different treatments, the per cent reduction of larval population over untreated check was highest in chlorantraniliprole @ 10 g a.i./ha (81.02%), followed by spinosad @15 ga.i./ha (78.13%) and indoxacarb @40 ga.i./ha (78.02%). The lowest per cent reduction was found in the plots treated with Bacillus thuringiensis (45.14%) and azadirachtin (45.52%). Among different treatments highest marketable yield was recorded in chlorantraniliprole (149.92q/ha) and the lowest marketable yield was observed in azadirachtin (98.1q/ha) and Bt (98.81q/ha). Incremental cost benefit ratio was maximum (1:18.44) in chlorantraniliprole followed by spinosad (1:16.33) and diafenthiuron (1:13.96). The lowest incremental cost benefit ratio was found with novaluron (1:2.48).

Keywords

Bioefficacy, Insecticides, Biopesticides, Plutella xylostella, Cabbage.

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Shruti Kaushal ¹, Pawan K. Sharma ¹, P. C. Sharma ¹

Affiliations
1 Department of Entomology, CSK Himachal Pradesh Krishi Vishvavidyalaya, Palampur - 176 062, IN

Abstract

The studies on seasonal abundance of sucking insect and mite pests infesting okra were undertaken at CSKHPKV, Palampur and farmers' field at Samloti during kharif 2018. The activity of two sucking pests i.e., aphid, Aphis gossypii and jassid, Amrasca biguttula biguttula on okra at Palampur initiated during second and third week of July, respectively and the pests remained associated with the crop till harvest i.e. third week of October. The peak population of A. gossypii (101.3aphids/plant) and A. biguttula biguttula (7.2 jassids/plant) was observed during second week of October and fourth week of August, respectively. Whereas, at Samloti the population of A. gossypii, A. biguttula biguttula and Tetranychus urticae started appearing during first week of June and the peak population of 64.4 aphids per plant was recorded during third week of September. The maximum number of jassids per plant (18.6) was observed during last week of August and T. urticae remained on okra crop for a short period having peak population of 11.2 mites per plant during second week of June. Analysis of correlation between weather factors and population of sucking pests on okra at Palampur showed that population of A. gossypii had a significant negative correlation with minimum temperature (r = -0.6545) and relative humidity (r = -0.7646). At Samloti, maximum temperature had significant negative effect on A. gossypii (r = -0.6040) and A. biguttula biguttula (r = -0.5144).

Keywords

Okra, Aphis gossypii, Amrasca biguttula biguttula, Tetranychus urticae, Weather Parameters and Seasonal Abundance.

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Harsimran Kaur ¹, Surender K. Sharma ¹, P. C. Sharma ¹

Affiliations
1 Department of Entomology, CSK Himachal Pradesh Krishi Vishvavidyalaya, Palampur - 176062, IN

Abstract

Shivalik region of Himachal Pradesh has a great diversity of pollen and nectar sources and good potential for commercial beekeeping. Studies on the morphological characteristics of pollen grains were carried out at Bee Research Station, Nagrota Bagwan of CSK Himachal Pradesh Agricultural University, Palampur, Himachal Pradesh during the year 2018-2019. This study was opined to explore 60 blooming plants of different group viz., oilseed crops, forest and fruit trees, vegetables and ornamental plants. Fresh and matured pollens were collected at the time of anthesis, washed with 70% ethyl alcohol and slides were prepared using DPX mountant. With an aid of Phase Contrast Microscope both polar and equatorial lengths of pollen as morphological features of 60 pollen types were described. The dominant pollen type belonged to family Rosaceae (8) followed by Brassicaceae (6), Asteraceae (4) and Verbenaceae (3).

Keywords

Pollen, Morphological Characteristics, Polar, Equatorial.

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