scholarly journals Requirement of heat unit and agrometeorological indices in selected wheat growing zones

MAUSAM ◽  
2021 ◽  
Vol 50 (1) ◽  
pp. 63-70
Author(s):  
A. KASHYAPI ◽  
H. P. DAS

Wheat growing ET -stations (viz., Jorhat, Varanasi, New Delhi, Ludhiana, Raipur, Jabalpur, Akola, Bellary, Banswara and Jodhpur) situated in arid to per humid climatic zones were selected. Heat unit and three agromeleorological indices, viz., ARI (agroclimatic rainfall index), YMI (yield moisture index) and AI (aridity index) were computed at various growth stages of wheat crop using latest available five years data for each of the stations. The study revealed that the crop degree days requirement varied from 1580 (at Jorhat) to 2350 (at Akola) with the maximum requirement at tillering and milk stages. All the stations (except Jorhat) recorded ARI values less than 25%, while for the stations in peninsular and western India, the values were even below 10%. Low cumulative YMI values were obtained in peninsular and western India, while high values were observed over eastern India. The wheat crop did not experience any aridity during tillering to flowering stages for all the stations (except Bellary and Banswara). High values of At were observed at early and late crop growth stages. Negative correlation was obtained between AI and ARI with the highest value (-0.89) observed at New Delhi. Depending upon this study, the wheat growing areas were divided into five zones.

MAUSAM ◽  
2021 ◽  
Vol 61 (4) ◽  
pp. 569-576
Author(s):  
A. KASHYAPI ◽  
A. L. KOPPAR ◽  
A. P. HAGE

The spatial and temporal distributions of heat unit and various agrometeorological indices for the rice crop, are studied in this paper. Eight ET – stations were selected from six rice growing zones, viz., Canning (in lower Gangetic plains), Bikramganj and Varanasi (in middle Gangetic plains), Ludhiana (in trans Gangetic plains), Ranchi, Shymakhunta (in eastern plateau and hills), Annamalai Nagar (in east coast plains and hill region) and Pattambi (in western plains and ghat region). Eleven crop growth stages were identified for this  study, viz., germination, nursery seedling, transplanting, tillering, active tillering, lag phase, panicle initiation, flowering, grain formation, grain maturity and harvesting, the duration of each of the growth stages varied widely, station wise. Daily data were collected growth stagewise for latest available five years and the mean values were computed for the derived parameters, viz., the crop requirements of heat unit, agroclimatic rainfall index (ARI), yield moisture index (YMI), aridity index (AI). The study revealed that for rice crop the total degree days requirement varied from 1706 degree – days (at Ranchi) to 2815 degree – days (at Shymakhunta). It showed primary peak (with 16.7 % of total requirement) at active tillering stage. The ARI values were mostly higher than 100 per cent. The mean YMI values varied widely from 477 mm (at Bikramganj) to 1523 mm (at Pattambi). The values showed main peak at active tillering stage. The AI values showed moderate aridity at early growth stages, which increased at advanced crop growth stages.


2020 ◽  
Vol 8 (5) ◽  
pp. 3026-3035

Manual examination is not as accurate to examine crop growing stages because of the possibility of the human mistake and errors. While machine examination or automatic examination can easily examine crop growing stages and increase productivity because it provides fast and accurate examine result. This study provide a solution to finding the wheat crop growth stages, Once the growing stages are established, farmers can take suitable and measured steps to improve the production of wheat or other agricultural crops. For finding the growth stages of wheat digital image processing technique is used. RGB model, HSI model, mean value of green colour, hue and saturation images use for examining wheat crop.


2014 ◽  
Vol 3 (4) ◽  
pp. 24-35 ◽  
Author(s):  
Sajjad Haider ◽  
Shahzada Adnan

Due to rapid growth of population, massive deforestation and anthropogenic activities, noticeable change in climate conditions is being observed in Pakistan. Increased aridity due to climate change is a growing environmental problem of the agricultural country like Pakistan. It is essential to assess and monitor aridity to combat the probable land degradation and drought desertification. Identification of arid and semi arid regions on climatic basis is the first essential step in any project of land reclamation for agricultural and other purposes. A geographic information system is used in this paper for the assessment of aridity in Pakistan from long term climatic data of fifty years (1960-2009) collected from fifty four stations situated in the country. In the delineation of climatic zones and delimitation of their boundaries, five well known aridity models viz. De Martonne Aridity index, Erinc Aridity index, Thornthwaite Precipitation Effectiveness index, UNESCO Aridity index and Thornthwaite Moisture index are utilized for this purpose. The study shows that southern parts of the country are dry and more vulnerable to drought while the northern parts have variable types of climate. Almost 75 to 85% of the total area of the country is arid in which most part lies in the south while less than 10% area is humid lies in the north of the country. This study will be a good predicator for agricultural scientist, agronomist and hydrologist to plan according the climate of the region.DOI: http://dx.doi.org/10.3126/ije.v3i4.11728International Journal of EnvironmentVolume-3, Issue-4, Sep-Nov 2014Page : 24-35 


MAUSAM ◽  
2022 ◽  
Vol 53 (4) ◽  
pp. 457-464
Author(s):  
S. SENGUPTA ◽  
H. P. DAS ◽  
A. A. KALE

The agrometeorological  data pertinent to estimation of water use and related agrometeorological indices of  KBSH - II (1988 to 1991) and MORDEN varieties of sunflower (1992 and 1993) cultivated both in rabi and kharif seasons, were used to understand the comparative water use pattern and agrometeorological indices for getting an idea about the crop condition at Bangalore. The study revealed that mean weekly water use was higher in almost all the years during the kharif season than during the rabi season except in  1990 and the consumptive water use increased with development of the vegetative cover of the crop reaching a peak value in the vegetative growth stage. The ARI (agroclimatic rainfall index) and cumulative YMI (yield moisture index) were always higher during the kharif season than correspondingly those during the rabi season and showed yearly and  seasonal variability in different growth stages which was due to the moisture stress condition of the soil as well as prevailing weather conditions of the atmosphere. In case of AI (aridity index), high values were observed at early and late crop growth stages during the kharif season which showed that the crop experienced less aridity between vegetative to seed formation  stage. The water use efficiency (WUE) of the crop also revealed wide variation due to variety and season.


2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Jonathan Willow ◽  
Liina Soonvald ◽  
Silva Sulg ◽  
Riina Kaasik ◽  
Ana Isabel Silva ◽  
...  

AbstractDouble-stranded RNAs (dsRNAs) represent a promising class of biosafe insecticidal compounds. We examined the ability to induce RNA interference (RNAi) in the pollen beetle Brassicogethes aeneus via anther feeding, and compared short-term (3 d) to chronic (17 d) feeding of various concentrations of dsRNA targeting αCOP (dsαCOP). In short-term dsαCOP feeding, only the highest concentration resulted in significant reductions in B. aeneus survival; whereas in chronic dsαCOP feeding, all three concentrations resulted in significant mortality. Chronic dsαCOP feeding also resulted in significantly greater mortality compared to short-term feeding of equivalent dsαCOP concentrations. Our results have implications for the economics and development of dsRNA spray approaches for managing crop pests, in that multiple lower-concentration dsRNA spray treatments across crop growth stages may result in greater pest management efficacy, compared to single treatments using higher dsRNA concentrations. Furthermore, our results highlight the need for research into the development of RNAi cultivars for oilseed rape protection, given the enhanced RNAi efficacy resulting from chronic, compared to short-term, dsRNA feeding in B. aeneus.


Weed Science ◽  
2014 ◽  
Vol 62 (4) ◽  
pp. 608-618 ◽  
Author(s):  
Martina Keller ◽  
Geoffroy Gantoli ◽  
Jens Möhring ◽  
Christoph Gutjahr ◽  
Roland Gerhards ◽  
...  

The effect of weed interference on corn yield and the critical period for weed control (CPWC) were determined in Germany and Benin. Treatments with weed control starting at different crop growth stages and continuously kept weed-free until harvest represented the “weed-infested interval.” Treatments that were kept weed-free from sowing until different crop growth stages represented the “weed-free interval.” Michaelis–Menten, Gompertz, logistic and log–logistic models were employed to model the weed interference on yield. Cross-validation revealed that the log–logistic model fitted the weed-infested interval data equally well as the logistic and slightly better than the Gompertz model fitted the weed-free interval. For Benin, economic calculations considered yield revenue and cost increase due to mechanical weeding operations. Weeding once at the ten-leaf stage of corn resulted already profitable in three out of four cases. One additional weeding operation may optimize and assure profit. Economic calculations for Germany determined a CPWC starting earlier than the four-leaf stage, challenging the decade-long propagated CPWC for corn. Differences between Germany and Benin are probably due to the higher yields and high costs in Germany. This study provides a straightforward method to implement economic data in the determination of the CPWC for chemical and nonchemical weed control strategies.


2021 ◽  
pp. 132-141
Author(s):  
Ashish Kumar Jangid

The Short-tailed ground agama or Hardwicke’s bloodsucker Calotes minor (Hardwicke & Gray, 1827) is known to occur in the Indian subcontinent and is largely confined to arid to semiarid environments, such as hard barren desert and abandoned fields. The precise distribution of this species is largely unknown to date, with few locality records spread biogeographically across Eastern Pakistan, Central and Western India. To improve on the existing spatial knowledge on this species and assess the ability to predict species distributions for taxa with few locality records, we studied the distribution of C. minor using a species distribution modelling framework. Our study allowed us to predict the distribution range of C. minor and help define a niche for this habitat-specific species. Highly probable habitats for C. minor were arid and semi-arid dryland habitats, characterised by plains or less rugged terrain with moderately narrow temperature range, lower aridity index, moderate to low vegetation index, and wide precipitation range. Furthermore, we report four additional occurrence records of C. minor from central Rajasthan.


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