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Goat Breeding Tips for Livestock Farmers (Urdu)

In order to get maximum meat and milk Beetal, Daira Deen Panah, Nachi, and Teddy Breeds.....

Mango Amazing Facts

The mango is known as the 'king of fruit' throughout the world. The name 'mango' is derived from the Tamil word 'mangkay' or 'man-gay'. When the Portuguese traders settled in Western India they adopted the name as 'manga'.

Pomegranate(Punica granatum) Cultivation and Farming

Pomegranates are fairly drought tolerant and can be grown on either calcareous or acid soils. Climate - Grow best in dry climates with mild winters. Chilling requirement

EU may also ban Monsanto GMO in wake of shocking cancer findings

Russia's consumer protection group, Rospotrebnadzor, said it was halting all imports of GM corn while the country's Institute of Nutrition will be evaluating the results of the study.

Protect Garden Pots during Winter

Many pots, especially ornamental containers that aren’t designed to stand outside in freezing temperatures, need winter protection. Wrap them up in burlap (possibly double layers), and secure tightly at the top and bottom with strong garden string.

Sustainable Agriculture and Fertilizers Practices in Pakistan

Agriculture is the mainstay of Pakistan’s economy. It has a total area of 79.61 million hectare, and the total area used for crop production is only 22 million ha.

Herbs For Winter Windowsill

Growing season is over, do you still find yourself ready to dash out to the garden for some chives, basil or a sprig of thyme...

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Wednesday, December 11, 2013

Anatomical Differences Between Crop and Weed

The amount of spray retention by foliage after postemergence applications can affect selectivity. This selectivity is usually due to the crop plant’s having a waxy cuticle that repels the spray solution.Examples include onions, peas, cereal grains, Brassica vegetable crops, and conifers. Medium to high spray volumes usually provide better selectivity, and adding an adjuvant can decrease selectivity as a result of enhanced adhesion of the spray droplets. Anatomical Differences Between Crop and WeedDifferences in leaf shape, size, and orientation between weed and crop can provide some selectivity differences. This is most common for controlling dicot weeds in small grain crops (the grain leaves retain less herbicide because of shape, orientation, size, and granular epicuticular wax). Postemergence selectivity can be due to the growing point of the crop being protected from direct contact by the herbicide while the growing point of the weed is exposed. The best example is dicot weed control (growing point not well protected by emerging leaves) in small grains (growing point well protected by the whorls of emerging leaves). The herbicide must not have a high degree of phloem mobility for this selectivitymechanism to work. For more detail regarding the influence of plant morphology on herbicide absorption, see the review by Hess (1987).

Preemergence selectivity can be due to a difference in root morphology between the weed and the crop. Grass weeds usually have a fibrous root system, whereas dicot crops usually have a taproot system. Thus,growth inhibitor herbicides, such as trifluralin, applied to the soil come directly in contact with the growing root tips in grass weeds, but not with those of the deeper-rooted dicot crops. For this selectivity mechanism to be useful, the water solubility and soil binding characteristics of the herbicide must be such that movement isrestricted to the upper soil profile.
Morphology differences within stem tissue of grass plants can provide differences in selectivity. The growing point of many grass weeds (crabgrass and wild oat) are more exposed to herbicide-treated soil than wheat and barley where the growing point is protected inside the coleoptile.

Sukkur Barrage canals to be closed from January 6

The Chief Engineer Sukkur Barrage Left Bank Sukkur Region has said that all the canals of Sukkur Barrage would be remained closed for the annual closure. He said that the closure will start from January 6 to 20, 2014 for the purpose of normal inspection, maintenance and necessary repair of the infrastructure.
Sukkur Barrage canals to be closed from January 6For that period there will be no water supply in any of the off-taking canal of Sukkur Barrage ie N.W. Canal, Dadu canal, Khairpur Feeder East canal, Khairpur Feeder West canal, Rohri Main canal, Nara canal and their allied channels, the Chief Engineer added.

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