Effects of repeated topical application of dichlorvos on blood enzymes and its toxicity in buffalo calves (Bubalus bubalis)

Dichlorvos was applied as spray at 1 and 2% concentrations daily for a period of 28 and 21 consecutive days, respectively to buffalo calves. Animals sprayed with 1% dichlorvos displayed mild to moderate clinical signs of toxicosis during the 4th week of exposure. The higher concentration (2%) produced clinical signs of poisoning after 12-16 applications, and was lethal to one of three animals. Daily spraying of dichlorvos at both concentrations inactivated erythrocyte cholinesterase (ChE) (15-21%), plasma ChE (17-20%) and serum carboxylesterase (5-10%) within 3 days. The extent of inhibition of esterases was increased with repeated treatment and maximal inhibition of erythrocyte ChE (80-89%), plasma ChE (81-91%) and serum carboxylesterase (33-54%) with 1 and 2% concentrations was observed on the 28th and 21st day after start of application, respectively. In surviving animals, blood esterases remained inactivated to the extent of 14-65% on the 14th day after the termination of treatment. Dichlorvos at both concentrations significantly (P less than 0.01) elevated the serum levels of aspartate aminotransferase, alanine aminotransferase, acid phosphatase and alkaline phosphatase. The activities of these enzymes in surviving animals recovered to control values within 14 days after the final application of dichlorvos.     

Isolation and Culture of Ovine and Bubaline Small and Large Pre-antral Follicles: Effect of Cyclicity and Presence of a Dominant Follicle

Studies were conducted to examine the effects of the cyclicity and the presence of a dominant follicle (DF) in ovary on the recovery and in vitro growth of pre-antral follicles (PFs) in sheep and buffalo. Small pre-antral follicles (SPFs, 100–250 μm) and large pre-antral follicles (LPFs, 250–450 μm) were isolated from slaughterhouse ovaries in the breeding seasons by a mechanical and enzymatic method. The sheep and buffalo PFs were cultured in vitro for 6 and 15 days, respectively, and examined for their growth, survival and antrum formation rates and growth rates of oocytes in cultured pre-antral follicles. The follicles of the sheep and buffalo were recovered and cultured simultaneously within replicates. The recovery rates (number per ovary) of both SPFs and LPFs were significantly (p < 0.05) higher in cyclic ewes (SPFs: 22.0 ± 3.3 vs 12.1 ± 2.6 and LPFs: 16.0 ± 3.6 vs 9.2 ± 1.8) and buffaloes (SPFs: 9.2 ± 1.3 vs 4.1 ± 1.0 and LPFs: 10.3 ± 2.7 vs 5.4 ± 0.7) compared with those recovered from acyclic ones. Presence of a DF in ovary significantly (p < 0.05) reduced the recovery rates of LPFs in ewes (9.06 ± 2.7 vs 16.4 ± 3.8) but had no effect in buffalo. Cyclicity of animals or follicular dominance had no effects on in vitro growth, survival and antrum formation rates and growth rates of oocytes in cultured PFs of SPFs and LPFs in both sheep and buffalo. The in vitro growth, survival and antrum formation rates of LPFs and growth rates of oocytes in cultured LPFs were significantly (p < 0.05) higher than those observed in SPFs in both sheep and buffalo. The overall recovery and growth rates of the PFs were lower in buffaloes compared with ewes.     

Microbial and chemical sources of phosphorus supply modulate the yield and chemical composition of essential oil of rose-scented geranium (Pelargonium species) in sodic soils

Rose-scented geranium (Pelargonium sp.) is a highly valued aromatic crop. Its growth is limited by soil salinity and sodicity stress. Arbuscular mycorrhizal (AM) fungus, phosphate-solubilizing bacteria (PSB), and P fertilizers may enhance the growth and secondary metabolism in geranium plants. In this context, a pot experiment was conducted to study the effects of PSB, AM fungi (Glomus intraradices), and P fertilizer on the yield, chemical composition of essential oil, and mineral element acquisition of geranium. The dry matter yield of shoot and essential oil yield, and mineral element (P, K, Ca, Mg, Na, Fe, Cu, and Zn) uptake in shoot tissues of geranium were significantly increased by the inoculation with AM fungi, co-inoculation with AM fungi and PSB, and P fertilization as compared to control. While the co-inoculation of geranium with AM fungi and PSB significantly enhanced the content of the monoterpenes such as citronellol, geraniol, geranial, and a sesquiterpene (10-epi-γ eudesmol), the P fertilization only enhanced the content of a sesquiterpene, 10-epi-γ eudesmol in the volatile oil. We conclude that the co-inoculation of PSB and AM fungi could be the best natural alternative to phosphate fertilizers to enhance the yield and quality of essential oil from geranium plants grown in sodic soils.     

Arbuscular Mycorrhizal （AM） Diversity in Prosopis cineraria （L.） Druce Under Arid Agroecosystems

Arbuscular mycorrhizal （AM） fungi associated with Prosopis cineraria （Khejri） were assessed for their qualitative and quantitative distribution from eight districts of Rajasthan. A total of three species of Acaulospora, one species of Entrophospora, two species of Gigaspora, twenty-one species of Glomus, seven species of Sclerocystis and three species of Scutellospora were recorded. A high diversity of AM fungi was observed and it varied at different study sites. Among these six genera, Glomus occurred most frequently. Glomus fasciculatum, Glomus aggregatum, and Glomus mosseae were found to be the most predominant AM fungi in infecting Prosopis cineraria. Acaulospora, G. fasciculatum, Sclerocystis was found in all the fields studied, while Scutellospora species were found only in few sites. A maximum of thirty-six AM fungal species were isolated and identified from Jodhpur, whereas only thirteen species were found from Jaisalmer. Spores of Glomusfasciculatum were found to be most abundant under Prosopis cineraria.     

Effect of Graded Levels of Nitrogen and Sulfur and Their Interaction on Yields and Quality of Aromatic Rice

ABSTRACT

In a greenhouse experiment, involving factorial combinations of nitrogen (N) (0, 15, 30, 45, and 60 mg kg^{? 1} soil) and sulfur (S) (0, 7.5, 15.0, 22.5, 30.0 mg kg^{? 1}soil), application of all levels of N and S 15 mg kg^{? 1} and above increased the grain yield of aromatic rice (Basmati cv. ‘Taraori’) significantly. The highest grain yield of aromatic rice was recorded from the treatment combinations of 60 mg N + 15 mg S kg^{? 1} or 45 mg N + 30 mg S kg^{? 1}. The interaction of N and S influenced the N and S content in rice grain, N content in straw, N: S ratio both in grain and straw, milling (%), and other quality parameters significantly. Milling (%) and hulling (%), thousand grain weight, L: B ratio, cooked grain breadth, and aroma score were found to be significantly and positively correlated with the N: S ratio of rice grain while grain breadth had a significant inverse relationship with N: S ratio in grain.     

Identification of dominant and recessive genes for resistance to Fusarium wilt in pigeonpea and their implication in breeding hybrids

Fusarium wilt is an important disease of pigeonpea [Cajanus cajan (L.) Millsp.] and it can cause severe yield losses. Chemical control of this disease is difficult and expensive; therefore, cultivation of resistant varieties/hybrids is the most efficient strategy for enhancing the production. In the present study, by using a wilt susceptible cytoplasmic-nuclear male-sterile line and four wilt resistant fertility restorers, one dominant and one recessive gene with dominant suppressive epistatic effects were found responsible for controlling resistance to Fusarium wilt. Considering the annual losses and wide spread nature of wilt diseases in pigeonpea, it is imperative that all the inbred and hybrid cultivars have high level of resistance to this disease. The presence of dominant gene for resistance will increase the efficiency of breeding wilt resistant cultivars because it will yield greater proportion of resistant genotypes in segregating generations. In hybrid breeding also, the presence of dominant gene for wilt resistance will be an advantage. The transfer of this gene in female hybrid parents will ease the breeding of wilt resistant hybrids because this will allow the use of both wilt resistant as well as susceptible restorers in generating wilt resistant hybrid combinations.     

Forage production and nitrogen nutrition in three grasses under coconut tree shades in the humid-tropics

Reduction in forage production (FP) under trees in the humid tropics is well known, but information on how different levels of nitrogen (N) fertilizer influence FP under trees is meager. The present study reports effects of four N fertilizer levels (0, 60, 80 and 120 kg ha⁻¹ N) on net soil N mineralization rate (NMR) and soil moisture (SM), FP, shoot biomass/root biomass ratio (SB/RB), N concentration in SB, N uptake and nitrogen use efficiency (NUE) of three grasses [guinea (Panicum maximum Jacq.), para (Brachiaria mutica (Forssk) Stapf) and hybrid-napier (Pennisetum purpureum Schumach.)] under three canopy positions [under canopy (UC, representing high shade), between canopy (BC, representing low shade) and open] of coconut trees (Cocos nucifera L.) in a coconut based silvopastoral system in the humid tropical climate of South Andaman Island of India. The study was performed for two annual cycles (2005–2006 and 2006–2007). The hypotheses tested were: (1) FP would decline under tree shades, both in N fertilized as well as no N fertilized conditions, when SM was not growth limiting in the open. However, amount of decline in the FP would depend on grass species and intensity of shades i.e., higher was the shade greater would be the decline; (2) N fertilizer would increase FP under tree shades, but the increase depended on grass species, intensity of shades and amount of N applied. Amount of N applied, however, would not annul the shades effects when SM was not growth limiting in the open. The study revealed that the tree reduced light 59% under UC and 32% under BC positions, but the N fertilizer levels increased NMR by 11–51% under UC and 3–44% under BC positions compared to the open. SM did not differ across the canopy positions. Under all situations, FP of all grasses declined under UC (47–78%) and BC (18–32%) positions compared to the open; the decline was greater in Hybrid-napier than Guinea and Para grasses. Forage production of all grasses increased with N fertilizer increments under all canopy positions reaching 32 t ha⁻¹ dry matters for hybrid-napier at 120 kg ha⁻¹ N in the open. Both guinea and para grasses outyielded hybrid-napier grass under UC but not under BC or in the open. N concentration in the forage (SB) also increased as N fertilizer level increased. These observations support our hypotheses and suggest that forage production under coconut palms can be increased by the application of N fertilizer with both guinea and para grasses being more productive than hybrid-napier grass under the high shade. Where light conditions are better, hybrid-napier would produce more forage than the other species.     

Disposition kinetics and dosage regimen of sulfapyridine in buffalo (Bubalus bubalis).

The disposition kinetics and dosage regimen of sulfapyridine were studied in buffalo calves following a single intravenous dose of 100 mg/kg. Distribution half-life (t1/2 alpha) elimination half-life (t1/2 beta) and Vd (area) was 0.181 +/- 0.008 h, 13.4 +/- 0.52 h and 0.59 +/- 0.03 L kg-1, respectively. Total body clearance, which represents the sum of all clearance processes, and tissue/plasma (T/P) ratio were calculated to be 31.1 +/- 2.28 ml kg-1 h-1 and 2.25 +/- 0.09, respectively. A satisfactory intravenous dosage regimen of sulfapyridine in buffalo would be 104 mg/kg followed by 75 mg/kg at 24 h intervals.