Harmful effects of weeds in paddy
Rice is a cereal grain belongs to the grass family of Graminae and native to the deltas of the great Asian rivers, the Ganges, the Chang (Yangtze), and the Tigris and Euphrates. The rice plant grows from 2 to 6 ft tall, with a round, jointed stem, long pointed leaves and edible seeds borne in dense head on separate stalks. Rice is one of the most cultivated grain crops in India as well as in Asian countries and a staple diet of major part of India. India is an important centre for rice cultivation and consumption. India stands in second position after China in the production of rice. Methods of growing rice differ greatly in different regions, but in most Asian countries including India, the traditional hand methods of cultivating and harvesting rice are still practiced. Modern farming of rice started in most of the countries which drastically reduced the labour problems and cost of cultivation.
Harmful Weeds of Paddy :
1 Variable flatsedge, is listed as the world’s worst weeds, being a problem especially in rice, sugarcane, tea and corn. Cyperus difformis is a plant of aquatic and moist habitats. It is a weed of rice fields . It blooms in the summer . This is an annual herb with one to many thin, soft erect stems reaching over 30 centimeters in maximum height. There are usually a few long, wispy leaves around the base of the plant. The inflorescence is a rounded bundle one to three centimeters wide, containing up to 120 spikelets. The flowers are light brown with areas darker brown and sometimes a yellowish or purplish tint.
2 Cyperus iria is also known as rice flat sedge and rice flatsedge. It is a smooth, tufted sedge found worldwide. The roots are yellowish-red and fibrous. The plant often grows in rice paddies, where it is considered to be a weed. C. iria is rated as one of the three most important weeds of rice in Sri Lanka, India and the Philippines. It is principally a weed of rice around the world. It is difficult to separate the competitive effects of C. iria from those of other components of the weed flora but the weed caused 40% yield reductions in rice.
3 Echinochloa crus-galli is a type of wild grass originating from tropical Asia that was formerly classified as a type of panicum grass. This plant can grow to 60″ (1.5 m) in height and has long, flat leaves which are often purplish at the base. Most stems are upright, but some will spread out over the ground. Stems are flattened at the base. The seed heads are a distinctive feature, often purplish, with large millet-like seeds in crowded spikelets. It is considered one of the world’s worst weeds, it reduces crop yields and causes forage crops to fail by removing up to 80% of the available soil nitrogen. The high levels of nitrates it accumulates can poison livestock. It acts as a host for several mosaic virus diseases.
How do farmers control weed in paddy field:
A herbicide is a chemical substance used to control or manipulate undesirable vegetation, especially weeds. Herbicides are extensively used in gardening, farming, and landscape turf management. Herbicides are classified into two categories: selective and non-selective. Selective herbicides kill specific unwanted plants while leaving desirable vegetation relatively unharmed. Non-selective herbicides kill all or most plant species.
HPM Chemicals & Fertilizers Ltd. is one of the main agrochemical providers in the nation, plans to help agriculturists experiencing crop harms because of terrible climate or insects and pests. The company has a range of products that oblige farmers searching for better quality create . HUNTER GR (Butachlor 5% GR) is a prominent herbicide that put a conclusion to weeds and stops their regrowth. It is a selective pre-emergence herbicide. It is used to control weeds of paddy. It controls Cyperus difformis, Cyperus iria, Echinochloa crusgalli, Echinochloa colonum, Eleusine indica ,Eclipta alba, Fimbristylis miliacea, Ludwigia purviflora, Sphenoclea zeylanica.