DSR TECHNOLOGY: Rice is one of the most important food crops in the world, and staple for more than half of the global population.
Looming water crisis, water-intensive nature of rice cultivation and escalating labour costs drive the search for alternative management methods to increase water productivity in rice cultivation. Direct seeded rice (DSR) has received much attention because of its low-input demand. It involves sowing pre-germinated seed into a puddled soil surface (wet seeding), standing water (water seeding) or dry seeding into a prepared seedbed (dry seeding).
In Europe, Australia and the United States, DSR is highly mechanised. The advancement of early-developing assortments and enhanced supplement the executive’s systems alongside expanded accessibility of synthetic weed control strategies has empowered numerous ranchers in the Philippines, Malaysia, Thailand and India to change from transplanted to DSR culture.
This move ought to significantly diminish edit water prerequisites, soil natural issue turnover, supplement relations, carbon sequestering, weed biota and ozone depleting substance discharges. In any case, weed invasion can cause substantial yield misfortunes in DSR.
What’s more, late occurrences of impact malady, edit lodging, debilitated part quality and stale yields over the years are significant difficulties in such manner. In this survey, we talk about the encounters, potential preferences and issues related with DSR, and propose likely future examples of changes in rice development.
Guide seeding of rice alludes to the way toward setting up a rice edit from seeds sown in the field instead of by transplanting seedlings from the nursery. There are three primary strategies for direct seeding of rice (DSR): dry seeding (sowing dry seeds into dry soil), wet seeding (sowing pre-developed seeds on wet puddled soils) and water seeding. Dry seeding has been the main technique for rice foundation since the 1950s in creating nations.
The appropriation of a direct-seeded strategy for swamp rice culture would essentially diminish expenses of rice creation. To date, no explicit assortments have been created for this reason. Existing assortments utilized for TPR don’t seem, by all accounts, to be all around adjusted for seedling development in an at first oxygen-drained microenvironment.
Accordingly, agriculturists frequently resort to the expensive routine with regards to expanding the seeding rate for DSR by 2– multiple times. New assortments reasonable for DSR must have the capacity to rise and develop from a non-overflowed soil.
DSR is a noteworthy chance to change creation practices to accomplish ideal plant thickness and high-water profitability in water-rare territories. Generally, rice is developed by transplanting one-month-old seedlings into puddled and persistently overwhelmed soil.
The benefits of the customary framework incorporate expanded supplement accessibility (e.g. press, zinc, phosphorus) and weed concealment. Concerning yield, both direct seeding (viz. wet, dry or water seeding) and transplanting had comparative outcomes.
A few difficulties go up against the wide-scale selection of DSR by agriculturists, for example, weed pervasion, stale yield, accessibility of intentionally created assortments, panicle sterility, supplement accessibility, irritations and sicknesses and water the board.
A record of each is given beneath.
High weed pervasion is the real bottleneck in DSR particularly in dry field conditions. TPR seedlings have an upper hand over recently developed weeds contrasted and rising DSR seedlings. What’s more, early weeds in TPR are controlled by flooding, not at all like in DSR.
In excess of 50 weed species pervade coordinate seeded rice, making significant misfortunes rice generation around the world. At the point when agriculturists change from TPR to DSR the weed verdure changes drastically. Weed species, for example, stable area grass and Asian sprangletop turn out to be increasingly common inside a couple of long periods of receiving direct-seeded, wet-sown rice.
During the 1970s, when DSR was brought into Malaysia and Vietnam, corral grass, Asian sprangletop and aromacca grass (Ischaemum rugosum L.) were not regular in rice fields however ruled rice fields by the 1990s. DSR frameworks additionally support variable level sedge (Cyperus difformis L.) and water plant (Sagittaria montevidensis L.) in Australia and USA, and Lindernia spp. in Asia.
In India, densities of corral grass, climbing dayflower (Commelina diffusa L.) and purple nut sedge (Cyperus rotundus L.) expanded in DSR contrasted and TPR in field tests from 2000 to 2004. In Pakistan, the recurrence of bermuda grass (Cynodon dactylon L.), climbing dayflower, purple nut sedge, rice level sedge and pony purslane (Trianthema portulacastrum L.) expanded considerably in DSR. As a rule, horse-purslane prompted finish disappointment of DSR rice trim (Farooq’s own perception).
DSR is exposed to more serious weed pervasions than TPR because, in dry-seeded rice, weeds sprout all the while with rice, and there is no water layer to stifle weed development. In DSR, weedy rice (Oryza spp.) turns into another significant weed to control. Phenoxy and sulfonylurea mixes are generally utilized herbicides in Malaysia, Vietnam and Thailand to control expansive leaved weeds and sedges in DSR.
Rates of weeds getting to be impervious to those herbicides are on the ascent; for instance, there is proof that weed species, for example, Shorea zeylanica (Thwaites) P. Ashton, overshadow clover (Marsilea minuta L.), and globe fringerush (Fimbristylis miliacea L.) have created protection from phenoxy herbicides. Further investigations on genotypic variety in weed resilience qualities including early seedling power and allelopathy would be beneficial.
Sicknesses and creepy crawly bugs
Rice is helpless to different maladies, rice impact being a standout amongst the most destroying, in both oxygen consuming and coordinate seeded societies. In any case, the seriousness of rice shoot increments submerged restricted conditions. In Brazil, impact opposition is the most imperative target attribute for reproducing programs in vigorous rice.
Water shortage and move from transplanting to coordinate seeding favours neck impact spread. Studies propose that the dimension of water supply impacts a few procedures, for example, spore freedom, germination and disease in rice impact pandemics.
Water the board specifically influences the harvest microclimate especially dew statement, which influences the lifecycle of the pathogen, and in a roundabout way influences edit physiology, accordingly, impacting host vulnerability.
Poor water the executives rehearses result in clammy or dry soil rather than overwhelmed or wet conditions favoring dew testimony and making nature vulnerable for host and impact advancement.
Here and there the assault of arthropod creepy crawly irritations is diminished in DSR contrasted and TPR, yet a higher recurrence of worn out trick infection, yellow orange leaf infection, sheath scourge and grimy panicle have been seen in DSR. Additionally, announced expanded assault of darker spot malady and plant containers in DSR contrasted and TPR.
The dirt borne pathogenic growth Gaeumannomyces graminis var. graminis has been seen in dry-seeded rice without supplemental water system in Brazil. Root-hitch nematodes have likewise been seen when changing from overflowed to water protection rice generation frameworks
Rice is drier season touchy than other grain crops amid blooming. Rice plants developed in both DSR and TPR frameworks are touchy to water shortage. Dry seeding is the most well-known technique for product foundation in DSR; rice develops on peripheral soil dampness contrasted and TPR (which has ceaseless standing water in the field often).
Subsequently any short scene of dry season, specifically amid the conceptive stage, might be more annihilating for plants brought up in DSR contrasted and TPR. Time to anthesis diminishes when panicle water potential declines, bringing about substantial scale panicle sterility.
Panicle transpiration opposition expanded rice spikelet richness amid blooming when water focused on. Diminished starch levels have been seen in anthers of plants presented to water pressure. The quantity of sterile spikelets expanded, and additionally failed, obscure and pale portions in DSR contrasted.
In DSR, infrequent yield decrease of oxygen consuming rice has been watched, however isn’t completely comprehended. It could be identified with ‘soil disorder’, possibly the joined impacts of allelopathy, supplement consumption, development of soil-borne irritations and illnesses, and soil basic corruption. In Brazil, for instance, plant autotoxicity is believed to be the reason for yield decay by consistently raising the harvest following dry seeding framework.
Corresponding author: firstname.lastname@example.org
I am working as Research Associate at University of Agriculture, Faisalabad, Pakistan. My research directions are Seed Enhancement, Storage and Seed longevity.