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71.
Ashish Bashyal Sandeep Shrestha Kishor P. Luitel Bhupendra P. Yadav Bed Khadka Jeffrey W. Lang Llewellyn D. Densmore 《水产资源保护:海洋与淡水生态系统》2021,31(9):2594-2602
- The Critically Endangered gharial (Gavialis gangeticus) residing within Bardiya National Park (BNP) in Nepal constitutes the sixth major sub-population of this unique lineage; however, this population is not well studied. A 46 km protected stretch of the Babai River and a 60 km stretch of the Karnali River in and around BNP were surveyed for gharials in early 2017 and in 2019.
- Gharial counts in 2017 – 17 from the Babai and one from the Karnali rivers – consisted of 10 adults, five sub-adults and three juveniles. In 2019, 19 gharials were counted – 18 for the Babai and one for the Karnali – comprising 11 adults, six sub-adults and two juveniles. In the Babai River within BNP, four breeding groups were identified. Gharials in BNP prefer sandy vs. rocky banks for basking and completely avoid sand-grass and clay banks. Habitat preference did not vary with size class.
- Protected stretches of both rivers inside BNP (76 km) have resident gharial, intact habitats and few human threats. In contrast, the unprotected stretch of the Karnali (30 km) is threatened by boulder quarrying, sand mining and unlicensed fishing, and is avoided by gharials despite the availability of habitat.
- This study established baseline data, including indices of population size, distribution and habitat preferences, and documented resident gharials that are breeding in the Babai River in BNP. The conservation of this Babai population is crucial for the species’ survival in BNP.
- Based on this study, we recommend the following conservation actions on the Babai stretch: (a) determine hatching success; (b) assess juvenile recruitment; (c) consider supplementation by releasing captives; (d) study riverine features important as baselines; (e) accommodate upstream movements on the protected Babai stretch; and (f) protect the downstream Babai outside the boundary of the BNP.
72.
A field experiment was conducted for two crop cycles during 2003–2005 and 2004–2006 at Indian Institute of Sugarcane Research, Lucknow to improve bud sprouting, dry matter accumulation (DMA), nutrient uptake and ratoon yield by using potassium fertilizer. Potassium (K) fertigation in standing plant cane increased the number of buds per stubble and number of stalks in ratoon cane. K content of stubble increased by 16.7% with K fertigation. The content of reducing sugars in buds at the time of ratoon initiation improved significantly with K fertigation. It improved dry matter accumulation, number of millable canes, individual cane weight, ratoon cane and sugar yields. Thus, it could be concluded that application of 66 kg K ha?1 with irrigation water in standing plant cane before harvest improved bud sprouting, dry matter accumulation and nutrient uptake in ratoon crop. Irrigation in standing plant cane increased ratoon cane (69.9 t ha?1) and sugar yields (7.6 t ha?1). This increase for ratoon cane and sugar yield was 8.7 and 5.55%, respectively over the control. Further, it increased ratoon cane yield by 15.21% (74.1 t ha?1) and sugar yields by 13.9% (8.2 t ha?1) with K fertigation over the control. Thus, K nutrition holds great promise for improving growth of ratoon cane and sugar yields. 相似文献
73.
Satyendra Kumar;Bhaskar Narjary;Kalpana Paudyal;Rajender Kumar Yadav;Sushil Kumar Kamra; 《Irrigation and Drainage》2024,73(3):928-943
Irrigation of rice using groundwater is considered one of the main contributors to north-west India's declining water level. The present study hypothesizes that zero-till direct seeding of rice (ZTDSR) with the optimum irrigation schedule may reduce irrigation compared to puddled transplanted rice (PTR). Crop growth stage-dependent predefined soil matric potential (SMP), that is, −15, −30 and −45 kPa based irrigation schedules either during the entire growing period or their combinations during the vegetative phase in ZTDSR, were compared with PTR for two consecutive seasons. The results showed that irrigation in ZTDSR at lower SMP at any growth stage caused adverse effects on yield. Irrigation at −15 kPa during the entire crop season with straw mulch was found to be the best schedule for ZTDSR. ZTDSR with −15 kPa irrigation, however, saved 36.2 cm of water and recorded higher water productivity but produced 20% less grain yield over the prevailing PTR. A higher groundwater system loss (GWSL) was found in the PTR (29.2 cm) than in the best ZTDSR (23.6 cm) schedule, which indicates better groundwater management in the ZTDSR than in the PTR. Hence, the ZTDSR has the potential to save irrigation, achieve higher water productivity and manage the depletion of groundwater resources in rice–wheat dominant north-west India. 相似文献
74.
Water stress after flowering, one of the major factors limiting yields of pearl millet, affects both seed setting and grain filling and is a consequence of more/less water used prior to anthesis. However, whether genotypes have different sensitivities for seed setting and filling under drought, if exposed to similar stress intensity, is unclear. Experiments were conducted in two pairs of pearl millet genotypes, that is, PRLT2/89‐33 and H77/833‐2, 863B and 841B, contrasting for terminal drought tolerance, and two genotypes, ICMR 01046 and ICMR 01029 (IL‐QTLs), introgressed with a terminal drought tolerance QTL from PRLT2/89‐33 into H77/833‐2. Total seed weight, panicle number, 100‐seed weight, seed number and stover biomass were measured at different soil moistures and throughout grain filling. Sensitive H77/833‐2 had higher seed number and yield under well‐watered (WW) conditions than in PRLT2/89‐33 and IL‐QTLs. Upon increases in water stress intensity, H77/833‐2 suffered losses mostly in stover biomass (45 %) and seed number (60 %) at 0.3 FTSW whereas the biomass and seed number of PRLT2/89‐33 decreased little (20 % and 25 %). The 100‐seed weight of H77/833‐2 decreased only 20 % under stress. Tolerant 863B also maintained a higher seed number and biomass under water stress than 841B. Grain filling duration in PRLT2/89‐33 and IL‐QTLs was similar to that of H77/833‐2 under WW conditions but lasted longer than in H77833‐2 under water stress (WS). Similarly, seed growth of 863B was longer than 841B under WS. It is concluded that the higher seed yield of tolerant parents PRLT2/89‐33 and 863B, and of IL‐QTLs under WS was explained by the retention of a higher number of seeds than in sensitive lines, while the decrease in the 100‐seed weight was proportionally less than the decrease in seed number. Phenotype with lesser number and larger size of panicles and larger grain size, like genotypes PRLT2/89‐33 and 863B, withstood post‐anthesis water stress better. IL‐QTL inherited part of these characteristics, indicating a role for the terminal drought QTL in maintaining larger seed number and higher 100‐seed weight. The continuous stover biomass increase under WW in H77/833‐2, due to tillering, might indicate that tiller growth and grains are in competition for resources after anthesis, and this may relate to the relatively shorter grain‐filling period. 相似文献
75.
Vikrant Dalal;Dhundwal Kamaldeep;Ankit Magotra;Dipin Chander Yadav;Sindhu Pushpa;Asha Rani Garg; 《Reproduction in domestic animals》2024,59(12):e14749
This study revealed the presence of single nucleotide polymorphisms in the CXCR1 gene and their association with performance traits and mastitis incidence in Murrah buffalo. The targeted SNP rs211042414 (T > C) at the g.106216468 locus in partial exon 2 of the CXCR1 gene was genotyped using PCR amplification and restriction enzyme digestion by Alu I, Bsa I, Dde I, Ava I, Hind III, EcoRV, Hae III, and Hae II restriction enzymes. The genotypic frequencies revealed three genotypes: CC, CT, and TT, with the C allele being the most prevalent (0.79) compared to the T allele (0.21). Targeted SNP showed significant association with the incidence of clinical mastitis incidence, and the study revealed that the TT genotyped animals showed a higher incidence of clinical mastitis compared to the TT and CT genotyped animals in the targeted population. Furthermore, least squares analysis revealed that targeted performance traits, viz. 305 days milk yield, total milk yield, and lactation length, were significantly associated with the genetic variants of the CXCR1 gene. TT genotyped animals exhibited higher milk yield than CT and CC genotyped animals, indicating a positive association between the T allele and increased milk production. These findings revealed that there is a scope for the genetic improvement of Murrah buffalo. Incorporating the identified CXCR1 gene polymorphisms into existing selection criteria can help to improve disease resistance and milk production traits in Murrah buffalo. However, further validation with a larger sample size is necessary to strengthen the observed associations and ensure their practical applicability. 相似文献
76.
Ajay Kumar Yadav Sagar Chandra Mandal Arun Bhai Patel Pradip Kumar Maurya 《Aquaculture Research》2019,50(11):3343-3349
An experiment was designed to evaluate the requirement of dietary protein for Reba carp, Cirrhinus reba fingerlings using semi‐purified diet. Five isocaloric diets were prepared containing 20%, 25%, 30%, 35% and 40% level of protein using casein, gelatin as a major protein source. The experiment was conducted for 105 days in triplicates to evaluate the growth, survival, feed utilization, carcass composition of C. reba. Mean weight gain was highest (p < .05) in T3. Specific growth rate was highest in T3 and lowest in T1. Similarly, significantly (p < .05) highest net fish yield were recorded in T3. No significant difference was recorded in survivability. Feed conversion ratio, protein efficiency ratio, feed conversion efficiency and protein conversion efficiency were significantly (p < .05) higher for T3 compared with other treatments. Highest carcass protein and lipid values were recorded in T3. So, conclusion can be drawn that 30% crude protein is optimum for overall performance. Furthermore, broken‐line analysis for specific growth rate, final biomass and net fish yield indicated that dietary protein level of 28.148 to 28.253% is optimum for the best growth performance of fingerling C. reba. 相似文献
77.
The equitable distribution of canal water is imperative to ensure social justice as well as crop productivity. In north-west India and Pakistan, water from the tertiary canal (watercourse) is distributed to the farmers through a rotational system of irrigation. In this system the duration of supply to each farmer is in proportion to his holding in the outlet (watercourse) command, without considering the seepage loss. The rate of seepage loss increases with increase in length of watercourse from head to tail. Thus, the farmers in the lower reaches get much less water per unit area than the farmers in the upper reaches. The farmers must be compensated for the seepage loss. Therefore, a model was developed to ensure equitable distribution of water to the farmers located on a watercourse in proportion to their land holdings giving due compensation for the seepage loss. The model is based on the assumption that soil throughout the length of flow is homogeneous and loss through evaporation is negligible. The model developed ensures an equitable distribution of water to the farmers according to their land holdings. A comparison of existing and revised time allocation reveals that the farmers located in the upper reaches were getting more time (up to 12.2 min per unit area), while the farmers located in the lower reaches have been getting less time (up to 28.1 min per unit area). The existing allocation of time of 0.75 h per unit area to all the farmers according to the old rules was revised to 0.546–1.219 h per unit area from head to tail. The conclusions drawn suggest that the strategy developed here should be adopted elsewhere in the existing system of irrigation for equitable distribution of canal water. Received: 21 December 1999 相似文献
78.
Mondal Santu Bhakat M. Singh A. Mohanty T. K. Abdullah M. Yadav S. K. Kumar R. 《Tropical animal health and production》2019,51(7):1823-1827
Zebu bulls are a shy breeder and they exhibit optimum libido in the presence of females with estrus phase. Continuous semen collection with the use of male dummy leads to lack of adequate sexual stimulation. Therefore, the present study was designed to test the effect of estrus-specific molecule(s) for effective sexual preparation of donor bulls. The bulls were divided into normal and poor libido group, five bulls in each group by taking 1-month control study data after collecting the information of individual bull’s sexual behaviour during semen collection by regular semen collector. The bulls were never being exposed to female animals and semen was collected by an artificial vagina. The ten animals were exposed to a glycerol-water solution (50/50 v:v) as control and then exposed to estrus-specific molecules one by one. The estrus-specific molecules like squalene, 1-iodoundecane, acetic acid, coumarin, propionic acid, oleic acid, and 2-butanone were purchased from Sigma-Aldrich Company, USA, and the molecules were solubilised individually in a non-pressurised aerosol dispenser as 1.0% concentration in glycerol-water solution (50/50, v:v). Identical bulls were used as the control and exposed to each molecule one by one by giving a refractory period of 14 days. A nasal spray of acetic acid or 2-butanone significantly (p < 0.05) reduced reaction time (RT) and total time taken to ejaculate (TTTE) in normal libido bull group. Semen volume, sperm concentration, and the total number of sperm per ejaculation obtained did not show significant improvement in the normal libido group of bulls after the application of estrus-specific molecules as compared to the control. In poor libido group, acetic acid, oleic acid, and 2-butanone application showed significant (p < 0.01) improvement in RT and TTTE as compared to the control group, whereas semen production variables like sperm concentration and total sperm output per ejaculation increased significantly (p < 0.05) except semen volume. There was significant (p < 0.01) reduction in RT (%) and TTTE (%) after the application of acetic acid followed by 2-butanone and oleic acid. The sperm concentration and total sperm output per ejaculation were more after the application of each molecule but significant increase (p < 0.05) in sperm concentration was observed with 2-butanone (11.42%), acetic acid (11.42%), and oleic acid (10.13%), whereas total sperm output per ejaculation increased significantly (p < 0.05) only after the application of acetic acid and 2-butanone (24.75% and 26.84%). Hence, it can be concluded that acetic acid, 2-butanone, and oleic acid are effective for better sexual preparation of Sahiwal bulls and total sperm output per ejaculation.
相似文献79.
Rashmi Aggarwal Aradhika Tripathi Anita Yadav 《European journal of plant pathology / European Foundation for Plant Pathology》2010,128(3):333-342
Tilletia indica Mitra is the causal agent of Karnal bunt of wheat, an important disease prevalent in several countries. The disease is internationally quarantined and the pathogen due to its heterothallic nature shows high variability. In the present study, we compared the pathogenic behaviour of various isolates of T. indica collected from different geographical locations of India and genetically characterized monosporidial (Ms) culture lines raised from these isolates of the pathogen. Pathogenic variability revealed existence of three pathotypes based on aggressiveness on a set of differential host genotypes. Monosporidial culture lines viz., 5 each from KB1, KB2, KB4 and KB5 and three lines of KB3 were established and analyzed genetically using 12 Universal Rice Primers (URPs). Amplification showed 98.44% polymorphism and primer URP 13R produced 100% polymorphic bands. Maximum similarity (83%) was between KB1MsB and KB1MsD as calculated by Jaccard’s similarity coefficient, whereas, minimum similarity was between KB1MsC and KB4MsB; KB1MsE and KB3MsA (46%). Three groups were formed among all Ms culture lines. One major group consisted of 13 lines with approximately 70% similarity, the second group consisted of 7 culture lines showing 55% similarity and the third group consisted of 3 Ms lines. URPs were able to differentiate the Ms culture lines raised from different T. indica isolates and the results indicated heterogeneity in the pathogen population. 相似文献
80.
Epidemiological studies on some gastrointestinal nematodes of sheep and goats in Karnal, Ambala and Rohtak districts of Haryana (India) revealed that Haemonchus contortus and Trichostrongylus spp. were responsible for parasitic gastroenteritis in these hosts. The adult parasites persisted in the host throughout the year and there was no indication of hypobiosis. The maintenance of the parasite population depended on a continuous cycle of infection between the host and the pasture. The agroclimatic conditions of the districts revealed that, in general, favourable weather conditions for the development and survival of the free-living stages of the parasites existed all year round. 相似文献