Ruminal and histological characteristics and nitrogen balance in lamb fed diets containing cactus as the only roughage

Tropical Animal Health and Production - This study examined rumen fermentation, histological, blood, and urinary characteristics as well as ammoniacal nitrogen concentration, pH, nitrogen balance,...     

Evaluation of reproductive parameters in male Neotropical bats during dry and rainy months in a specific area of the Cerrado biome

The aim of this study was to analyse the reproductive aspects of male bats of three common species of the Phyllostomidae family: Artibeus lituratus, Platyrrhinus lineatus and Sturnira lilium, during dry and rainy months in a specific area of the Cerrado biome. Body weight was significantly higher during the dry months for S. lilium. The gonadosomatic index (GSI) and testicular weight were not significantly different between dry and rainy periods. The tubular parameters were significantly bigger in A. lituratus than in the other two species during both periods. No difference in the tubular/interstitial ratio was observed in any of the species during both periods. In both periods, all sperm cells and germ cell developmental stages were visible on seminiferous tubules whereas sperm cells were observed in epididymides of all sampled animals. The percentage of morphologically normal sperm was low (35%–60%), with no difference between periods. Spermatozoa from A. lituratus presented a leaf-shaped head, while the head was round-shaped in the other two species. In conclusion, our data suggest that males from the three studied species did not present reproductive latency during the most critical weather periods (dry and rainy months) in the metropolitan region of Brasilia, Brazil.     

Growth attributes,xylem sap composition,and photosynthesis in common bean as affected by nitrogen and phosphorus deficiency

The effects of nitrogen (N‐) and phosphorus (P‐) deficiency, isolatedly or in combination, on growth, nitrogenous fraction, and inorganic phosphate in xylem exudade, and photosynthesis of common bean (Phaseolus vulgaris L. cv. Negrito) were investigated. Plants were grown in nutrient solution adjusted daily to pH 5.5 and aerated continuously. Ten days after emergence mineral deficiency was imposed. Plants were then supplied with high N (7.5 mol m^‐3) or low N (0.5 mol m^‐3), and also with high P (0.5 mol m^‐3) or low P (0.005 mol m^‐3). All sampling and measurements were made 28 days after emergence. N‐ or P‐deprivation brought about large decreases in total leaf area by inhibiting the emergence of new leaves and primarily the expansion of the leaves. The specific leaf area did not change under N‐ but decreased under P‐limitation. The decreased shoot to root ratio in all deficiency treatments was a consequence of a lowering mass of above‐ground organs, especially of leaves.

The content of chlorophylls declined significantly only under N‐deficiency alone; carotenoids declined under both N‐ and combined N‐ and P‐limitation. No alteration in amino acid concentration in xylem exudate occurred in plants experiencing N‐starvation, while ureides increased by 79%, and nitrate and inorganic phosphate decreased greatly. Under P‐deprivation, amino acids and nitrate in xylem sap dropped by about half; ureides were held relatively constant, and phosphate was severely depressed. Total upward translocation of N through xylem was estimated to be about 16% higher in N‐deficient plants than in plants without mineral limitation, but leaf N levels in the former were lower as compared to control plants. The net carbon (C) assimilation decreased similarly regardless of the imposed deficiency treatment. Such a decrease was mainly determined by non‐stomatal factors. In general, no additive effect between N‐ and P‐limitation on any of measured parameters was observed.     

Dynamics of Agricultural Information and Effect on Income of Melon Farmers in Enugu-Ezike Agricultural Zone of Enugu State,Nigeria

ABSTRACT

The study assessed effects of agricultural information on the income of melon farmers. Ninety melon farmers constituted the sample for the study. Data were collected through an interview average annual income of the respondents from melon only was ?7,455.4, while their total average schedule, while percentage mean score and correlation were used in the analysis. Findings reveal that the monthly income was ?1,223. About 62 and 42% of the respondents, respectively, did not receive information on melon production and general agriculture. Thus, a positive and significant relationship exists between the number of times respondents received information on melon/general agriculture and their incomes.     

Antigenotoxicity and Antioxidant Activity of Acerola Fruit (Malpighia glabra L.) at Two Stages of Ripeness

Genotoxic and antigenotoxic effects of acerola fruit at two stages of ripeness were investigated using mice blood cells. The results show that no ripeness stage of acerola extracts presented any genotoxic potential to damage DNA (Comet assay) or cytotoxicity (MTT assay). When antigenotoxic activity was analyzed, unripe fruit presented higher DNA protection than ripe fruit (red color) extract. The antioxidant capacity of substances also showed that unripe samples inhibit the free radical DPPH more significantly than the ripe ones. The results about determination of compounds made using HPLC showed that unripe acerola presents higher levels of vitamin C as compared to ripe acerola. Thus, vitamin C and the complex mixture of nutrients of Malpighia glabra L., and especially its ripeness stages, influenced the interaction of the fruit extract with the DNA. Acerola is usually consumed when ripe (red fruit), although it is the green fruit (unripe) that has higher potential as beneficial to DNA, protecting it against oxidative stress.     

Geno-phenotypic diversity in a natural population of Hancornia speciosa Gomes: implications for conservation and improvement

Genetic Resources and Crop Evolution - Hancornia speciosa Gomes is native tree to South America, and its fruits are a source of income for communities and the food industry. The reduction of...     

Inheritance and heritability of resistance to citrus leprosis

ABSTRACT The genetic inheritance of resistance to leprosis, the most important viral disease of citrus in Brazil, was characterized through the phenotypic assessment of 143 hybrids resulting from crosses between tangor 'Murcott' (Citrus sinensis x C. reticulata) and sweet orange 'Pêra' (C. sinensis), considered to be resistant and susceptible to the disease, respectively. All plants were grafted onto Rangpur lime (C. limonia) and inoculated with Citrus leprosis virus, cytoplasmic type through the infestation with viruliferous mites, Brevipalpus phoenicis. The experiments were arranged in a completely randomized block design with 10 replicates. Incidence and severity of the disease in leaves and stems as well as plant growth parameters (plant height and stem diameter) were recorded for 3 years after the infestation with the viruliferous mites. The average values of all variables were analyzed using principal component analysis, discriminant factorial analysis, estimation of the clonal repeatability coefficients, and frequency of the distributions of the average values for each measured variable. The principal component analysis resulted in the identification of at least two groups with resistance and susceptibility to leprosis, respectively. About 99% of all hybrids were correctly classified according to the discriminant factorial analysis. The broad-sense heritability coefficients for characteristics associated with incidence and severity of leprosis ranged from 0.88 to 0.96. The data suggest that the inheritance of resistance to leprosis may be controlled by only a few genes.     

Understanding the Enemy: A Review of the Genetics,Behavior and Chemical Ecology of Varroa destructor,the Parasitic Mite of Apis mellifera

Varroa destructor (Mesostigmata: Varroidae) is arguably the most damaging parasitic mite that attacks honey bees worldwide. Since its initial host switch from the Asian honey bee (Apis cerana) (Hymenoptera: Apidae) to the Western honey bee (Apis mellifera) (Hymenoptera: Apidae), Varroa has become a widely successful invasive species, attacking honey bees on almost every continent where apiculture is practiced. Two haplotypes of V. destructor (Japanese and Korean) parasitize A. mellifera, both of which vector various honey bee-associated viruses. As the population of Varroa grows within a colony in the spring and summer, so do the levels of viral infections. Not surprisingly, high Varroa parasitization impacts bees at the individual level, causing bees to exhibit lower weight, decreased learning capacity, and shorter lifespan. High levels of Varroa infestation can lead to colony-wide varroosis and eventually colony death, especially when no control measures are taken against the mites. Varroa has become a successful parasite of A. mellifera because of its ability to reproduce within both drone cells and worker cells, which allows populations to expand rapidly. Varroa uses several chemical cues to complete its life cycle, many of which remain understudied and should be further explored. Given the growing reports of pesticide resistance by Varroa in several countries, a better understanding of the mite’s basic biology is needed to find alternative pest management strategies. This review focuses on the genetics, behavior, and chemical ecology of V. destructor within A. mellifera colonies, and points to areas of research that should be exploited to better control this pervasive honey bee enemy.     

Genome-wide association study for spot blotch resistance in Afghan wheat germplasm

Spot blotch (SB), caused by Bipolaris sorokiniana, is a devastating disease of wheat globally, especially in South Asia and South America. Understanding the genetics of resistance to SB is important for developing breeding strategies to improve resistance. A panel of 301 genotypes from Afghanistan was phenotyped over two crop seasons using a mixture of virulent B. sorokiniana isolates and genotyped using DArTSeq to obtain genome-wide markers. Fifty genotypes (16.6%) showed disease scores less than the resistant control. Principal component analysis using the genotypic data clustered the genotypes into five different groups. Among models used for genome-wide association mapping, the multilocus mixed model, and fixed and random model circulating probability unification algorithms were most effective in identifying significant marker-trait associations (MTA). Twenty-five MTAs at p ≤ .001 were identified on chromosomes 1A, 1B, 1D, 2B, 2D, 3A, 3B, 4A, 5A, 5B, 6A, 7A, and 7D, indicating the quantitative nature of resistance to SB. Phenotypic variation explained by these markers ranged from 2.0% to 17.7%, and genomic regions on the chromosomes 1D, 2D, 3A, 3B, 4A, 5A, and 5B coincided with loci identified in previous studies. Three single nucleotide polymorphism (SNP) markers on chromosomes 1B (SNP 1113207) and 5A (SNPs 5411867 and 998276) were significant in both crop seasons as well as in the combined analysis across seasons. Marker 5411867 is close to Vrn-A1, shown to be associated with SB in previous studies. Furthermore, among known SB resistance genes, Sb2 on chromosome 5B was predicted to be significant in this panel.