: Twenty-two strains of the tobacco caterpillar, Spodoptera litura (F.) (Lepidoptera : Noctuidae), collected from groundnut crops of eight locations in Andhra Pradesh, India, between 1991 and 1996 were assayed in the F1 generation for resistance to commonly used insecticides. Resistance levels ranged as follows : cypermethrin, 0É2-to 197-fold ; fenvalerate, 8-to 121-fold ; endosulfan, 1-to 13-fold ; quinalphos, 1-to 29-fold ; monocrotophos, 2-to 362-fold and methomyl, 0É7-to 19-fold. In nearly all strains pre-treatment with the metabolic inhibitor, piperonyl butoxide, resulted in complete suppression of cypermethrin resistance (2-to 121-fold synergism), indicating that enhanced detoxiÐcation by microsomal P450-dependent monooxygenases was probably the major mechanism of pyrethroid resistance. Pre-treatment with the synergist DEF, an inhibitor of esterases and the glutathione S-transferase system, resulted in a 2-to 3-fold synergism with monocrotophos indicating that esterases and possibly glutathione S-transferases were at least to some extent contributing to organophosphate resistance.

Pigeonpea [Cajanus cajan (L.) Millsp.] seed stored in triple layer Purdue Improved Cowpea Storage (PICS) bags for eight months retained germination and seed integrity significantly better than seed stored in traditional gunny bags. PICS bags prevented major damage caused by bruchids (Callosobruchus maculatus F.), while grain stored in gunny bags suffered severe losses. The aflatoxin levels in stored seed were low and not significantly different between the two storage systems. The levels of O 2 in PICS bags artificially infested with C. maculatus dropped rapidly during the first month of storage while the levels of CO 2 increased. Even in absence of bruchids (noninfested seed) PICS bags preserved seed germination for extended periods of time better than gunny bags; possibly due to the higher and more stable relative humidity inside the PICS bags. Higher seed germination would result in improved plant stands in the field and subsequent higher yields and increased productivity. Thus, PICS bags have shown potential to positively impact the economy of pigeonpea farmers in the semi-arid tropics.

Developmental thresholds and thermal rcqulrernents for different stages of Spodoptera litura iF.j fed on groundnut leaves were determined under constant laboratory conditions and in the field. .%n average of tiJ degretdtvs (DD) above a thrahold of E w u required from oviposition to egg hatch. the larval penod rqulred 503 DD and p~lpal stage 155 DD above a 10Y: threshold; females needed 29 DD above a 10.-threshold from emergence to ov~position. Fifth and s~xth instan accounted for about 50% of the total larval requirement under laboratory and field conditions. The response of various stages of S. lirura to temperatura under constant laboratory conditions was slmilu to that under heid condi-t~ons. The upper developmental threshold temperature of all staga was 37C; JOY: was lethal. KEY WORDS Insecta. Spodoptera htura. threshold temperatures. thermal requlrementr Spodoptera litura (F.) is an important pest of Jorhi. B. C. & C. RM P-d. 1975. N u m kernel as an antifeedent against the tobacco caterpillar (Spodoptmu litum F.). Phytoparasitica 3. 59-61. Mipahim, K. 19'71. Effect of ctnutant .ad Bwtuting tempemturn on the development of S~M Itturn-(F.) (Lapidoptun: Noctuidae). Appl Entomol. ;tboL 6(3): 105-111.-Prurd, J. & A. K. Bhatuchaqa. 1980. Land head m p k s of t k tobrmo aterpillar Spodopv Itturn (F.). Indian J. Entornol. 42:-7.

a b s t r a c tGroundnut seeds are prone to quality deterioration and damage due to improper storage. Hermetic storage of pods offers a novel, sustainable and ecologically safe alternative over traditional methods. In this paper, we demonstrate the efficacy of triple-layer "Purdue Improved Crop Storage (PICS)" bags, (that comprises of two inner high density polyethylene bags and one outer woven polypropylene bag), for protecting pods from quality deterioration, damage by bruchids (Caryedon serratus) and aflatoxin contamination (Aspergillus flavus). Custom made triple-layer bags were used and pods (of cv ICGV 91114) were placed @ 2 kg/bag. Over four months of storage under ambient conditions, triple-layer bags supported retention of seed weight, germinability and oil content significantly better than cloth bags. Further, under both natural and artificial infestations with A. flavus, seed aflatoxins levels were lower in PICS bags compared to cloth bags. Toxin accumulation in PICS bags deliberately infested with bruchids and A. flavus was less compared to cloth bags under similar conditions. Bruchid damage to pods was less in PICS bags versus cloth bags in all cases. Our results suggest the superiority of triple-layer PICS bags over cloth bags in protecting seed viability, seed weight and oil content while safeguarding the groundnuts from bruchids and retarding toxin accumulation.

The single cell gel electrophoresis (SCGE) assay, also known as the comet assay, is a cytogenetic technique for measuring and analyzing DNA single stranded breaks (SSB) and/or alkali labile sites within individual cells. Peripheral blood leukocytes of 22 oral squamous cell carcinoma (OSCC) patients were subjected to SCGE and the DNA damage levels (SSB) were quantified with respect to clinical staging and histopathologic grading. Highly statistically significant differences in DNA damage levels were found between normal subjects and patients with OSCC of the same age group. DNA damage levels were altered in all clinical stages and histopathological grades of oral squamous cell carcinoma. The differences were generally significant between all the clinical stages of OSCC, while in histopathologic grading the results were significant only between grades I and III. The results support the concept of a systemic host response in malignancy.