Bonment.com

?

water requirments of differrent crops and animals

by ghulam mohyuddin wani

chief consultant animal husbandry

NRAA, NEW DELHI

?

?

?

Introduction

?

In our previous treatise in www.article .com we have discussed the water requirements of animals.? Here we shall discuss the water requirements of different crops and compare it with the requirements of animals.? We will also discuss water use-determinants like soil-moisture, profile in determining the water requirements of a crop along with calculations for evaluating evaporation & transpiration losses during cropping clander & lastly increment for the presence of left moisture of the fallows.

?

Factors effecting water utilization

?

Water requirements of a crop are determined by various factors like soil moisture, texture, wind velocity, humidity, rainfall, temperature solar radiation, crop species, variety of as crop, cropping season, & other known and unknown factors both biotic and abiotic.? Rice crop utilization is estimated at 640 mm per hac in Pakistan.? The similar study estimates for wheat are lower than rice 330 mm.? Thus a rice- paddy rotation in Lahore, Punjab is estimated at 970 mm of water.? One wonders what the essence e of 970 mm of water is and how mud quantity of water is needed per hectare or per kg of grain.? Few reports of Johl, 2002 & others have given different estimates which will be discussed under following heads.

(a)??? Water requirements per hectare of land for producing various crop variety

(b)?? Calculation of water requirements- how they are made

(c)??? Water requirements of animals & a comparison with crops

The water requirements are measured by various methods.? We have to consider soil profile, soil moisture stored in the root zone of the planted crop, evaporation rate, humidity, temperature & all those factors described in preceding pages.? On an estimated basis different crops need water at following rates (Johl, 2002) table I

?

Table 1.??? Total water requirement per hectare

Crop????????????????????????????????????? water required in liters/ hac

Rice??????????????????????????????????????? 60,20,000

Wheat????????????????????????????????? 35,00,000

Cotton????????????????????????????????? 78,50,000

Sugar cane????????????????????????? 1,60,00,000

Sunflower?????????????????????????? 65,00,000

Kharif Maize?????????????????????? 46,00,000

Kharif Moong??????????????????? 41,50,000

Gobi Sarsoon???????????????????? 34,50,000

Winter Maize???????????????????? 61,50,000

?

Herian quoting Johl, 2002, reports the conversion of water in terms of kgs of grains as follows:

?

Table 1.? Water requirement per kg of grain harvested

Grain /Crop??????????????????????? water required in liters/ kg

??????????????????????????????????????????????? ?grain produce

Wheat ???????????????????????????????? 781

Rice??????????????????????????????????????? 1131

Kharif Maize?????????????????????? 1691

Gobi Sarsson????????????????????? 2851

Suflower ???????????????????????????? 5672

Cotton????????????????????????????????? 6217??????

Kharif Moong??????????????????? 8645

Summer Moong?????????????? 10,246

?

For calculating water requirements of crops, the calculatio0ns are made on the presumptions & a study of NSW department of primary industries as follows; for rice.

The duration of crop growth varies with the variety used.? Some of the Australian rice varieties mature in short time.? However water requirements differ during different stages of the crop growth.? Thus the varietal gestation days & days taken from planting to flowering & from flowering to physiological maturity needs to be taken into consideration.

Water requirements of rice depend upon variety and temperatures around the fields duration of growth is describe as panicle initiation to flowering & from flowering to maturation. ?For medium grain rice this panicle to maturity cycle duration is around 70-80 day ( white worth, 2006).? This period can be broken into panicle to flowering 30-35 days in short & long grain varieties grain in Australia.? However it is 5 days less (25-30 days)? in whorl season varieties Jerrah.? Flowering to physiological maturity days ranges from 35-45 days in all the varieties.? The total days of watering rice thus depends on the stage of development and the gestation days of the varieties.? We have most of the varieties maturing in 70-100 days in India.? These days exceed in temperate climatic conditions.? Sometimes cold waves & frost bites hinder ripening and the days of gestation get extended.? Therefore it is recommended to have on evaluation pilot study if exact requirements of water by each crop are intended.