Inoculum Level and Inoculation Method Influences on the Pathogenic Activities of Meloidogyne incognita in Studied Model Plant Okra (Abelmoschus esculentus L. Moench)

Agricultural activities such as watering crops with nematode-infested water from wells and boreholes, and using infected plant debris as manure or mulch increase root-knot nematode infection. So, this study aims at assessing the influence of the inoculation method and inoculum level of Meloidogyne incognita on the development of root galls on okra plants. Two M. incognita inoculation methods (suspension of individuals and galled root explants) and six inoculum levels (0, 10, 100, 500, 1000 and 2000 second-stage larvae/plant) were studied. The gall index, total numbers and reproductive factor of M. incognita were used to assess the effect of treatments on root gall development. Unlike the reproductive factor, gall index and the total numbers of M. incognita increased with their inoculum level. The pathogenic activities of M. incognita were most significant when crop soils were infested with galled root explants. However, an inverse relationship was found between the inoculum levels of M. incognita and the okra plant’s development. It is reflected by negative correlation coefficients ranging from -0.90 to -0.62. It is therefore important to burn roots infected with root-knot nematodes left in fields so that they do not act as an inoculum for crops.

Reproductive health and wellbeing: complementary to each other

Generally, women’s health receives attention only during pregnancy and the immediate post-partum period. A women’s health agenda was first articulated at the Fourth World Conference on Women held in Beijing in 1995. In the resulting Beijing Declaration and Platform for Action, a roadmap for gender equality and women’s empowerment was outlined, with a major focus on reproductive and sexual health (SRH) issues, which were the main killers of women then. Present study was carried out in order to find out the reasons of Reproductive Health and wellbeing problem in women children between the age group of 1-6 years and to provide results based remedial solutions and interventions. For this purpose, samples were selected from different villages of nine states in India which includes Assam (Jorhat), Andhra Pradesh (Hyderabad), Haryana (Hissar), Himachal Pradesh (Palampur), Uttar Pradesh (Pantnagar), Rajasthan (Udaipur), Maharashtra (Parbhani), Punjab (Ludhiana), Karnataka(Dharwad) Tamil Nadu (Madurai), Meghalaya (Tura). The wellbeing of women covers five major aspects on physical, social, emotional, spiritual and intellectual. Data analysis was done using frequency, percentage distribution. Results revealed that in the maximum states, the reproductive factor was average only two state were having good reproductive health. Parbhani, and all the states were having average wellbeing of women.

Reproductive factors and lung cancer risk: a comprehensive systematic review and meta-analysis

Background A number of studies have investigated the association between reproductive factors and lung cancer risk, however findings are inconsistent. This meta-analysis aimed to evaluate the association between female reproductive factors and lung cancer risk. Methods We conducted a comprehensive systematic search to identify relevant and eligible studies published before 18th December 2019. Inter-study heterogeneity was assessed using the Q test and I2 statistic. Based on the heterogeneity of each reproductive factor, fixed or random effects models were used to calculate the summary odds ratios (ORs) and 95% confidence intervals (CIs). Subgroup analyses by study design, lung cancer subtypes, smoking status, and ethnicity were also performed. Results A total of 66 studies with 20 distinct reproductive factors were included in this meta-analysis. Comparing the highest and lowest categories (reference) of each reproductive factor, parity (OR = 0.83, 95% CI = 0.72–0.96), menstrual cycle length (OR = 0.79, 95% CI = 0.65–0.96), and age at first birth (OR = 0.85, 95% CI = 0.74–0.98), were significantly associated with a lower risk of overall lung cancer. On the contrary, non-natural menopause was significantly associated with higher lung cancer risk (OR = 1.52, 95% CI = 1.25–1.86). Among never-smokers, a significant negative association was found between parity and lung cancer risk. Both parity and non-natural menopause were statistically significant in case-control studies. Conclusion These results suggest that certain reproductive factors may be associated with lung cancer risk. Future studies should further validate the associations, and investigate the underlying mechanisms.

Nematicidal Effect of Some Botanical Extracts for the Management of Meloidogyne incognita and on Growth of Tomato

Tomato (Solanum lycopersicum L.) is an important and widely grown vegetable crop all over the world. Although tomato is nutritionally and economically important, its production is constrained by biotic and abiotic constraints leading to poor marketable quantity and quality worldwide. Root-knot nematodes are one of the major pests affecting tomato production worldwide, especially, in the tropical and sub-tropical regions. Green house experiments were laid out in Complete Block Design (CBD) with a 3x7 factorial arrangement replicated three times carried out at the Department of Crop and Environmental Protection, University of Agriculture. The soil was sterilized before the experiment. Fresh leaves and seeds of Moringa oleifera, Ricinus communis and Jatropha curcas were washed with tap water, 15 g from each of leaves and seeds of the different botanicals was macerated separately in an electric blender at high speed for 4 minutes in 100 ml distilled water. The mixtures were passed through a Whatman filter paper number 1; the filtrates of the leaves/seeds were then collected. Three tomato varieties viz: Roma Vf, Rio Grande and UC82B were inoculated with approximately 5,000 freshly hatched second stage juvenile of Meloidogyne incognita, two weeks after transplanting. Thirty percent aqueous extract each of Castor, Moringa and Jatropha leaves and seeds was used, while double distilled water (0%) served as the control. Thirty ml of each leaf and seed aqueous extract was applied, 48 hours after inoculation as soil drench. Application was done at 1 weeks intervals thereafter for a period of 16 weeks. Data collected include number of fruits per plant, root gall index, nematode reproductive factor, and final nematode population. The results showed that various Moringa oleifera, Ricinus communis and Jatropha curcas leaves and seed extracts significantly (P<0.05) reduced root gall index, final population of M. incognita in the soil and nematode reproductive factor than the control. Application of the various treatments Moringa oleifera, Ricinus communis and Jatropha curcas led to significant increase in mean number of fruits and mean fruit weight yield of all the three tomato varieties. Therefore, the application of leaf and seed aqueous extracts of Moringa, Jatropha and Castor will serve as good alternative for the management of root knot nematode Meloidogyne incognita.

Vine Cuttings Technique for Evaluating the Reaction of Dioscorea rotundata Varieties to Root-Knot Nematodes

Root-knot nematodes (Meloidogyne spp.) contribute to low productivity and post harvest losses of white yam (Dioscorea rotundata). This study evaluated yam cultivars for resistance to Meloidogyne spp. using plants generated from single node vine cuttings. Forty accessions of D. rotundata were selected for the study and laid out in a randomized complete block design with 10 plants per replicate, three replicates and two treatments (Meloidogyne-inoculated and uninoculated). Vines were planted in vertically hanging bags and inoculated four weeks after with 500 eggs of Meloidogyne spp. Plants were harvested sixteen weeks after inoculation and data were collected on weight of tubers, nematode populations in tubers and soil, and nematode damage to tubers. Vine survival was up to 60%, although inoculated vines had lower rates of survival. All the surviving vines produced tubers of various sizes which differed between the control inoculated tubers. Based on galling index (damage) and reproductive factor, five accessions were designated as resistant with the remaining accessions being susceptible. The use of vine-cuttings was found to be effective for screening yam varieties for resistance to Meloidogyne spp.

Effects of Clariva Complete Beans Seed Treatment on Heterodera glycines Reproduction and Soybean Yield in Iowa

In recent years, nematode-protectant seed treatments have become available to supplement resistant soybean cultivars to manage soybean cyst nematode (Heterodera glycines; SCN). Twenty-seven small-plot and 18 strip-trial experiments were conducted comparing the effects of Clariva Complete Beans (CCB) and CruiserMaxx Advanced plus Vibrance (CMV) on SCN reproduction and soybean yield on a moderately resistant (2014) and resistant (2015 to 2016) soybean cultivar. Yield data were collected, and an SCN reproductive factor was calculated by dividing final (at harvest) SCN egg population densities by initial (at planting) population densities from soil samples collected in each small plot or sampled area in the strip trials. Relative to the CMV treatment, CCB significantly decreased SCN reproductive factor in two small-plot experiments (one each in 2014 and 2015) but not in any of the strip trials in any year. Soybean yields were significantly greater with CCB versus CMV in 5 of the 18 strip trials but not in any of the small-plot experiments, even when there were significant decreases in SCN reproduction. For unknown reasons, CCB significantly decreased yields in two small-plot experiments and at one strip-trial location. In summary, the effects of CCB seed treatment on SCN reproduction and soybean yields were variable in the years that these experiments were conducted in Iowa.

Host Preference and Seedborne Transmission of Ditylenchus weischeri and D. dipsaci on Select Pulse and Non-Pulse Crops Grown in the Canadian Prairies

The stem nematode Ditylenchus weischeri was recently reported on creeping thistle (Cirsium arvense) in Canada. Two greenhouse studies examined host suitability of crops commonly grown in the Canadian Prairies for D. weischeri and the closely related parasite of many crops, D. dipsaci. In the first study, common pulse crops (yellow pea, chickpea, common bean, and lentil), spring wheat, canola, creeping thistle, and garlic were evaluated. Plant biomass and reproductive factor (Rf = nematode recovered/inoculated) 8 weeks postinoculation were used to determine host suitability. Creeping thistle biomass was reduced by D. weischeri whereas D. dipsaci reduced biomass of four of five pea and two of three bean varieties. Two pea varieties were weak hosts for D. weischeri, with Rf slightly >1. D. weischeri aggressively reproduced on creeping thistle (Rf = 5.4). D. dipsaci reproduced aggressively on garlic (Rf = 6.4; a known host), moderately on pea varieties (Rf > 2), and weakly on chickpea and bean (Rf > 1). In the second study, using creeping thistle and yellow pea, D. weischeri was recovered from aboveground parts of the plants and seed of the former and D. dipsaci from the later. The results show that D. weischeri parasitizes creeping thistle but not other crops and that D. weischeri host preference is different from that of D. dipsaci.

Host status and phenotypic diversity of rice cultivars resistant to Meloidogyne species under glasshouse conditions

Five pot trials were carried out under glasshouse conditions to assess the host response of some selected rice cultivars to Meloidogyne javanica, M. paranaensis and M. enterolobii, based on nematode reproductive factor (RF) and number of nematodes (g root)−1. We also determined the broad-sense heritability and variance component estimations associated with M. paranaensis and M. incognita resistance. In addition, cluster analysis of cultivars was conducted. All cultivars were rated as susceptible or highly susceptible to M. javanica and highly resistant to M. enterolobii. To M. paranaensis, only cvs IAPAR 177 and BRS Caravela were resistant. From the principal component analysis and Ward’s cluster analysis, we obtained four conspicuous clusters of cultivars according to Meloidogyne species resistance, which demonstrates the variability of the genetic material studied. Higher broad-sense heritability values for RF and nematodes (g root)−1 were obtained. Taken together, our findings suggest that improvement of resistance of rice to Meloidogyne species resistance is possible. The implications for management programmes are also discussed.