Deep learning-based approach for identification of diseases of maize crop.

In recent years, deep learning techniques have shown impressive performance in the field of identification of diseases of crops using digital images. In this work, a deep learning approach for identification of in-field diseased images of maize crop has been proposed. The images were captured from experimental fields of ICAR-IIMR, Ludhiana, India, targeted to three important diseases viz. Maydis Leaf Blight, Turcicum Leaf Blight and Banded Leaf and Sheath Blight in a non-destructive manner with varied backgrounds using digital cameras and smartphones. In order to solve the problem of class imbalance, artificial images were generated by rotation enhancement and brightness enhancement methods. In this study, three different architectures based on the framework of 'Inception-v3' network were trained with the collected diseased images of maize using baseline training approach. The best-performed model achieved an overall classification accuracy of 95.99% with average recall of 95.96% on the separate test dataset. Furthermore, we compared the performance of the best-performing model with some pre-trained state-of-the-art models and presented the comparative results in this manuscript. The results reported that best-performing model performed quite better than the pre-trained models. This demonstrates the applicability of baseline training approach of the proposed model for better feature extraction and learning. Overall performance analysis suggested that the best-performed model is efficient in recognizing diseases of maize from in-field images even with varied backgrounds.

Chemopreventive and anticarcinogenic effects of Momordica charantia extract.

The aim of the study was to examine whether Momordica fruit extract (MFE) and Momordica leaves extract (MLE) might exert any chemopreventive effect in a two stage protocol in skin carcinogenesis with Swiss albino mice. The tumour incidence, tumour yield, tumour burden and cumulative no. of papillomas were found to be higher in the controls (without either extract) as compared to the MFE or MLE treated experimental groups. In a melanoma model, the mice which received fruit and leaf extracts of Momordica at the doses of 500 and 1000 mg/kg body weight for 30 days showed increase in life span of animals and tumour volume was significantly reduced as compared to control values. In cytogenetic studies, a single application of Momordica extracts at doses of 500, 1000 and 1500 mg/kg body weight, 24 hours prior the i.p. administration of cyclophosphamide, significantly prevented micronucleus formation and chromosomal aberrations in a dose dependent manner in bone marrow cells of mice. The present study demonstrate chemopreventive potential of Momordica fruit and leaf extracts on DMBA induced skin tumorigenesis, melanoma tumour and cytogenicity.

Anticarcinogenic effects of Solanum lycopersicum fruit extract on Swiss albino and C57 Bl mice.

In the present studies, the effect of Solanum lycopersicum extract on DMBA induced skin papillomas and B6 F10 melanomas was studied. Topical single application of DMBA at the dose of 4 mg/kg b.wt. followed by 1 % croton oil for 16 weeks produced a 100% incidence of skin papillomas which started appearing from the 6th week onwards. The mice which additionally received S. lycopersicum extract at 0.6 g/kg 2 day/week for 16 weeks showed a significant decrease in the number and incidence of tumors (p<0.05), with a delay in their appearance to week 10. Histopathological examination showed well and poorly differentiated squamous cell carcinomas in the group which received DMBA + Croton oil treatment whereas hyperkeratosis and hyperplasia were more prevalent in DMBA + Croton oil + Lycopersicum extract treated animals. In a second experiment the effect of cyclophosphamide alone and in combination with S. lycopersicum extract was studied in B16F10 melanoma tumour bearing mice. The inhibition rate was 25.9% in the cyclophosphamide treated group but this increased to 37.7% with S. lycopersicum. The life span of tumour bearing animals was also increased. Thus in two models, S. lycopersicum extract exerted protective potential against skin tumors.

Evaluation of anticarcinogenic and antimutagenic potential of Bauhinia variegata extract in Swiss albino mice.

BACKGROUND: Infusions from the bark of Bauhinia is used to treat various diseases in the traditional medical system of India and decoction of the roots is used in dyspepsia and act as an antidote to snake poison. Its chemopreventive potential for cancer was the subject of the present study. MATERIALS AND METHODS: To evaluate the anticarcinogenicity and antimutagenicity of Kachanar extract a skin carcinogenesis and melanoma tumour model was used, along with micronucleus and chromosomal aberration tests, in Swiss albino mice. RESULTS: In the skin papilloma model, significant prevention, with delayed appearance and reduction in the cumulative no. of papillomas was observed in the DMBA + Kachanar + croton oil treated group as compared to the DMBA + Croton Oil group. C57 Bl mice which received a 50 % methanolic extract of Kachanar extract at the doses of 500 and 1,000 mg/ kg body weight for 30 days showed increase in life span and tumour size was significantly reduced as compared to controls. In antimutagenicity studies, a single application of Kachanar extract at doses of 300, 600 and 900 mg/kg dry weight, 24 hours prior the i.p. administration of cyclophosphamide (at 50 mg/kg) significantly prevented micronucleus formation and chromosomal aberrations in bone marrow cells of mice, in a dose dependent manner. CONCLUSIONS: Our results suggest that Kachanar extract exerts anticarcinogenic and antimutagenic activity.

Hepato-toxic effect of diuron in albino rats.

Tumour initiating/promoting effect of diuron, a widely used substituted urea herbicide, was studied in rats using liver tumour model. Chronic exposure to diuron at a dose of 250 mg/kg body wt resulted in high mortality and weight loss in treated animals. The animals which received diuron + HCH treatment showed an increase in size and weight of liver as compared to controls. Liver tumours were not observed in any of the treated group whereas some significant histological changes were seen in diuron treated rat liver. Diuron thus has been found to be hepatotoxic albeit neither tumour initiating nor promoting in rat liver tumorigenesis assay system.

Prevention of chromosomal aberration in mouse bone marrow by indole-3-carbinol.

In this study, we report the protective effect of indole-3-carbinol (I3C), one of the glucobrassicin derivative isolated from cruciferous vegetables against cyclophosphamide induced chromosomal aberrations in mouse bone marrow cells. The three test doses namely 1000,500 and 250 mg/kg b.wt. of I3C provided protection when given 48 h prior to the single i.p. administration of cyclophosphamide (50 mg/kg). I3C alone did not induce chromosomal aberrations at the test doses of 1000 and 500 mg/kg b.wt.. Thus tested glucobrassicin derivative seems to have a preventive potential against cyclophosphamide induced chromosomal aberrations in Swiss mouse bone marrow cells at the doses tested.

Induction of chromosomal aberrations by propoxur in mouse bone marrow cells.

Propoxur is a widely used dithiocarbamate insecticide. In this study, the clastogenic effect of propoxur has been evaluated using chromosomal aberration assay in mouse bone marrow cells. Single i.p. administration of propoxur, at 25 mg/kg b.wt., a maximum tolerated dose (MTD) and 12.5 mg/kg b.wt (50% of MTD) have significantly induced different types of aberrations after 24 h of treatment. The aberrations were dose and time dependent and reached a maximum after 24 h of exposure. The results suggest a genotoxic potential of propoxur.

Prevention of cyclophosphamide-induced micronucleus formation in mouse bone marrow by indole-3-carbinol.

Indole-3-carbinol (I3C) is a glucobrassicin derivative isolated from cruciferous vegetables. In this study, the protective effect of 13C is reported against cyclophosphamide (CP)-induced micronuclei formation in mouse bone marrow cells. The three test doses, namely 500, 250 and 125 mg/kg body weight of 13C provided protection when given 48 hr prior to the single ip administration of cyclophosphamide (50 mg/kg). The efficacy of the test doses of 13C was also evaluated using a lower dose of CP (25 mg/kg body weight). A significant inhibition in micronuclei formation was noticed with 13C at 250 and 125 mg/kg body weight dose. 13C could not induce micronuclei formation at the test doses 500 and 250 mg/kg body weight. 13C, therefore seems to have a preventive potential against CP-induced micronuclei formation in Swiss mouse bone marrow cells.

Assessment of mutagenic potential of thiram.

Thiram is a widely used dithiocarbamate fungicide. In this study, the mutagenicity of thiram was investigated using the micronucleus and dominant lethal tests in Swiss albino mice. A single ip injection of 100 mg thiram/kg body weight, which is the maximum tolerated dose (MTD), significantly induced micronucleus formation in bone marrow cells after 30 and 48 hr of exposure; 50% and 25% of the MTD also induced micronucleus formation after the above time periods. A significant number of dead implants were induced when thiram was given to male mice in the diet at 10% of the oral LD50 during the whole spermatogenesis cycle (8 wk); this post-implantation loss indicates a dominant lethal mutation.

Assessment of mutagenic potential of propoxur and its modulation by indole-3-carbinol.

Propoxur is a widely used dithiocarbamate pesticide. In the present set of investigations, mutagenicity of propoxur (in formulation) was studied using the micronucleus assay in bone marrow of Swiss mice. Single intraperitoneal (i.p.) administration of 25 mg/kg body weight dose of propoxur, which is a maximum tolerated dose (MTD), significantly induced the micronucleus formation in bone marrow cells after a 24- and 48-hr exposure. A half and a quarter of the MTD (12.5 and 6.25 mg/kg) were found ineffective to induce the micronuclei formation after 24- and 48-hr time periods by the i.p. route. However, the PCE:NCE ratio was inhibited significantly with all the dose levels at both time periods. Oral administration of propoxur at different dose levels also induced micronuclei formation. A single application of 50 and 25 mg/kg dose levels of propoxur, which are MTD and 50% of MTD, also significantly induced micronuclei formation after 24- and 48-hr time periods in bone marrow cells of Swiss mice as compared with solvent control group, whereas a 12.5 mg/kg dose of propoxur was ineffective in inducing micronuclei formation. Single application of indole-3-carbinol (I3C), a glucobrassicin derivative present in cruciferous vegetables, significantly inhibited the propoxur-induced micronuclei formation when it was given at the dose level of 500 mg/kg body weight 48 hr before the single application of propoxur. Therefore, it seems that propoxur is mutagenic in the above test systems and I3C inhibited the mutagenicity of propoxur significantly.

Effect of diuron on germ cells of mice.

Diuron in both, acute (340 and 170 mg/kg body wt) and chronic (3400 ppm) doses induced dominant lethal mutations in male Swiss albino mice. The results suggest that diuron is mutagenic in dominant lethal test system.

Micronucleus induction by diuron in mouse bone marrow.

Diuron, a widely used substituted urea herbicide, induced the formation of micronuclei in bone marrow cells of Swiss mice. A single i.p. dose of 340 mg/kg b.w. diuron which is maximum tolerated dose (MTD) increased significantly the number of micronuclei at 30 h and 48 h time period. The dose of 170 mg/kg b.w. also induced the micronuclei formation in the above time period. However, a dose of 85 mg/kg b.w. was ineffective at the time periods studied. No induction of micronuclei was observed at 72 h time period after all the doses of diuron studied as compared to the solvent control. The diuron-induced frequency of micronucleated erythrocytes was independent of the sex of the test animals.

Tumour-promoting effect of chilli extract in BALB/c mice.

In 50% of BALB/c mice pretreated with atropine, tongue tumours were induced by fortnightly application of DMN-OAc (2 mg/kg) on the tongue. When DMN-OAc + TPA was used for the initiation-promotion protocol, tumours were observed on the tongue, the site of application, in only 10% of animals. In the same group, stomach tumours were obtained in 63% of mice, denoting that initiation-promotion could be successfully used to induce stomach tumours. Using a protocol of DMN-OAc + chilli as a promoter, we observed induction of stomach tumours. The promoter effect of chilli extract was also seen in the BHC-induced hepato-carcinogenesis system. It thus appears that, in BALB/c mice, chilli acts as a promoter in stomach and liver carcinogenesis.

Chilli extract treatment and induction of eye lesions in hamsters.

On chronic administration of 20 microliter of chilli extract to the cheek pouch of hamsters till death, 23% of the hamsters developed shrunken eye balls and closing of the eyelids. This effect was not observed in hamsters which received a single application of the potent carcinogen methylacetoxymethyl nitrosamine (DMN-OAC) (2 mg/kg body wt.) prior to repeated treatment with chilli extract. Vitamin A levels decreased significantly in the liver tissue of chilli-treated and carcinogen + chilli-treated groups compared to absolute alcohol-treated and untreated groups, while serum Vitamin A values decreased only in the DMN-OAC + chilli-treated group. However, Vitamin A levels do not seem to be linked causally with the effect on the eyes of chilli-treated hamsters, because these hamsters had circulating levels of Vitamin A comparable to those observed in untreated and alcohol-treated groups.