DEPARTMENT OF AGRONOMY COLLEGE OF AGRICULTURE, DAPOLI DR. BALASAHEB SAWANT KONKAN KRISHI VIDYAPEETH, DAPOLI ___________________________________________________________________________________ Name of the student : Mr. KANKAL VIJAY YADAVRAV Regd. No. : 156 Degree : Ph.D.(Ag.) Discipline : Agronomy Research Guide : Dr. U. V. Mahadkar Director of Research, Dr. B.S.K.K.V, Dapoli. Dist. Ratnagiri. Thesis Title : Effect of establishment techniques, weed control and integrated nutrient management on growth, yield and quality of drilled rice (Oryza sativa L.) Year of the award of degree : 2015 ABSTRACT Two years research experiment was conducted during Kharif season of 2013 and 2014 to investigate the, “Effect of establishment techniques, weed control and integrated nutrient management on growth, yield and quality of drilled rice (Oryza sativa L.),” at Agronomy Farm, College of Agriculture, Dapoli, Dist. Ratnagiri (M.S.). The soil of the experimental plot was clay loam in texture, moderately acidic in reaction, high in organic carbon content. It was medium in available nitrogen, low in available phosphorus and fairly high in available potassium. In respect of micronutrients the soil was deficient in available zinc, boron and molybdenum content during the both years of experimentation. The field experiment was laid out in split-split plot design comprising 36 treatment combinations replicated thrice. Main plot treatment consisted of four crop establishment techniques, raised bed dry seed sowing (E ), 1 raised bed sprouted seed sowing (E ), flat bed dry seed sowing (E ) and flat 2 3 bed sprouted seed sowing (E ). The sub plot treatment consisted, unweeded 4 control treatment (W ), weed free check (hand weed at 20, 40 and 60 DAS) 1 (W ) and pre-emergence application of oxadiargyl @ 0.12 kg/ha + post- 2 46 emergence application of bispyribac-sodium @ 0.025 kg/ha (W ) while, sub- 3 sub plot treatment comprised of three fertilizer management methods, recommended dose of fertilizer + FYM 5 t/ha (F ), recommended dose of 1 fertilizer + micronutrient foliar spray of Zn, B and Mo (F ) and recommended 2 dose of fertilizer + FYM 5 t/ha + micronutrient foliar spray of Zn, B and Mo (F ). 3 During the course of present investigation, periodical growth observations, weed study, yield contributing characters and yield were recorded to evaluate the treatment effects. The concentration of macro (N, P and K) and micronutrients (Zn, B and Mo) and its uptake by the rice and concentration of macronutrients (N, P and K) in weeds and its uptake was studied. Economics of the treatment combinations was also worked out. The experimental results revealed that plant count of rice/0.5 m length at 20 DAS and at harvest was non significantly influenced due to all treatments. But on ha basis significantly the highest plant population was recorded in flat beds than raised beds. Rice crop established by flat bed sprouted seed sowing technique recorded numerically higher growth and yield attributes. These attributes along with significantly higher plant population resulted into significantly higher grain and straw yield over the techniques of raised bed dry seed sowing and raised bed sprouted seed sowing. Weed density, dry weight of grass, broad leaved and sedge weeds and total dry weight of weeds were not found significantly influenced by various establishment techniques. Flat bed sprouted seed sowing gave significantly higher values of macro and micronutrients uptake over technique of raised bed dry seed sowing. The available status of macro and micronutrients after harvest of experimental crop was not differed significantly by various crop establishment techniques. The quality parameter i.e. protein content was also non significantly influenced by various establishment techniques. In case of economics, it was observed that flat bed sprouted seed sowing recorded significantly the highest gross returns of ₹ 62150 and ₹57268/ha, net returns of ₹ 4847 and ₹1075/ha, and numerically maximum 47 benefit cost ratios of 1.09 and 1.02 during the years 2013 and 2014, respectively. Among different weed control methods, treatment weed free check found significantly superior for all the growth parameters and yield attributing characters over unweeded control and was found statistically at par with the treatment of pre-emergence application of oxadiargyl @ 0.12 kg/ha + post- emergence application of bispyribac-sodium @ 0.025 kg/ha. The grain yield, straw yield and protein content were significantly enhanced and recorded higher values under treatment of weed free check than unweeded control and was statistically at par with the treatment of pre-emergence application of oxadiargyl @ 0.12 kg/ha + post- emergence application of bispyribac-sodium @ 0.025 kg/ha. The mean density and dry weight of monocot, broad leaved and sedge weeds at 40, 60, 80 DAS and at harvest, were significantly maximum under treatment unweeded control and significantly the lowest in weed free check which was followed by treatment pre-emergence application of oxadiargyl @ 0.12 kg/ha + post- emergence application of bispyribac-sodium @ 0.025 kg/ha which were at par each other during both the years of investigation. The highest and the lowest weed index values were recorded by unweeded control and pre-emergence application of oxadiargyl @ 0.12 kg/ha + post- emergence application of bispyribac-sodium @ 0.025 kg/ha, respectively. Weed free check recorded the highest weed control efficiency. Significantly higher N,P and K content in grain and straw and their uptake in grain, straw and their total uptake by rice was found in weed free check followed by treatment of pre-emergence application of oxadiargyl @ 0.12 kg/ha + post-emergence application of bispyribac-sodium @ 0.025 kg/ha which were at par with each other but significantly superior than unweeded control during both the years of study. Micronutrient content were found non significant in grain and straw whereas uptake of these nutrients by grain and straw total uptake by crop showed same trend as that of macronutrients uptake under both the years of study. 48 Unweeded control recorded significantly the highest and weed free check significantly the lowest N, P, K content and their removal by weeds over remaining weed control methods. The availability of macro and micronutrients in soil after crop harvest was found non significant during both years. With respects to economics weed free check gave significantly the highest gross returns followed by treatment pre-emergence application of oxadiargyl @ 0.12 kg/ha + post-emergence application of bispyribac-sodium @ 0.025 kg/ha which was statistically at par each other but significantly superior over unweeded control during both years. Weed free check gave significantly the highest net returns (₹ 6,362/ha in 2013 and ₹ 3,249/ha in 2014) over unweeded control. The highest values of benefit :cost ratio (1.13 and 1.08 in 2013 and 2014, respectively) were recorded by treatment pre- emergence application of oxadiargyl @ 0.12 kg/ha + post- emergence application of bispyribac-sodium @ 0.025 kg/ha. Fertilizer management method of recommended dose of fertilizer + FYM 5 t/ha + micronutrient foliar spray of Zn, B and Mo (F ) found 3 significantly superior for all growth parameters and most of yield attributing characters than treatment recommended dose of fertilizer + FYM 5 t/ha (F ) 1 and was at par with the treatment recommended dose of fertilizer + micronutrient foliar spray of Zn, B and Mo (F ) during both the years of 2 experimentation. The grain and straw yield were significantly enhanced and recorded higher values under treatment recommended dose of fertilizer + FYM 5 t/ha + micronutrient foliar spray of Zn, B and Mo (F ) than treatment 3 recommended dose of fertilizer + FYM 5 t/ha (F ) and was remained at par 1 with treatment recommended dose of fertilizer + micronutrient foliar spray of Zn, B and Mo (F ) during both the years of experimentation. 2 Weed density of grasses, broad leaved weeds, sedges and their dry weight at harvest were not differed significantly during both the years. Moreover, no much variation was observed in weed control efficiency. However, less weed index (%) value were recorded in treatment of 49 recommended dose of fertilizer + FYM 5 t/ha + micronutrient foliar spray of Zn, B and Mo (F ). 3 The macro and micronutrients content in rice grain, straw and protein content of grain gave numerically higher values whereas, uptake of macro and micronutrients by grain and straw and total uptake by crop showed significantly the highest values in treatment recommended dose of fertilizer + FYM 5 t/ha + micronutrient foliar spray of Zn, B and Mo (F ). The 3 availability of macro and micro nutrients in soil after crop harvest was also found non significantly influenced during both the years of study. From economics it is seen that, treatment recommended dose of fertilizer + FYM 5 t/ha + micronutrient foliar spray of Zn, B and Mo (F ) gave 3 significantly the highest gross monetary returns over treatment recommended dose of fertilizer + FYM 5 t/ha (F ). The treatment 1 recommended dose of fertilizer + micronutrient foliar spray of Zn, B and Mo (F ) gave significantly the highest net monetary returns (₹10,927 and 2 ₹8,521/ha in year 2013 and 2014, respectively) over rest of the treatments during both the years. The economic profitability was also achieved in this treatment (1.22 and 1.17 benefit:cost ratio in year 2013 and 2014, respectively). In respect of economics of different treatment combinations, the maximum gross monetary returns (₹ 78,311/ha during 2013 and ₹ 71,953/ha during 2014 were obtained in flat bed sprouted seed sowing with weed free check and supplied with recommended dose of fertilizer + FYM 5 t/ha + micronutrient foliar spray of Zn, B and Mo i.e. E W F and net monetary 4 2 3 returns in treatment combination of E W F i.e. flat bed sprouted seed 4 3 2 sowing with pre-emergence application of oxadiargyl @ 0.12 kg/ha + post- emergence application of bispyribac-sodium @ 0.025 kg/ha and supplied with recommended dose of fertilizer + micronutrient foliar spray of Zn, B and Mo of ₹ 24,312/ha during 2013. The highest B:C ratio of 1.50 and 1.42 were recorded by treatment combination E W F i.e. flat bed sprouted seed sowing with pre-emergence 4 3 2 application of oxadiargyl @ 0.12 kg/ha + post- emergence application of 50 bispyribac-sodium @ 0.025 kg/ha and supplied with recommended dose of fertilizer + micronutrient foliar spray of Zn, B and Mo over rest of treatment combinations. 51 CHAPTER I INTRODUCTION Rice (Oryza sativa L.) is the most important staple food grain crop of the world which constitutes the principle food for about 60 per cent of the world‟s population. In India, rice cultivation contributes to the total food grain production by 43 per cent and to the total cereal grains production by 46 per cent. The Asia-Pacific region produces and consumes more than 90 percent of the world‟s rice. Rice based production system provides the income and employment for more than 50 million households.Therefore rice is not only a staple food of the region but also a way of life. Rice believed to have originated in Asia. Ancient records showed that the Greek were introduced rice in India around 326 B.C. from there, it spread across Europe for the next 2000 years. It was brought to the new world (South and North America) by European settlers in the late 17th century. Domesticated rice belongs to Gramineae family with two species, Oryza sativa and Oryza glaberrima, Oryza sativa is native to tropical and subtropical southern Asia and African rice, Oryza glaberrima is native to West Africa. Studies have been suggested that there are three groups of Oryza sativa cultivars. The short grained „Japonica‟ or „Sinica‟ varieties by Japanese rice, the broad grained „Javanica‟ varieties, which thrive under tropical condition and „Indica‟ from South East Asia. Rice is cultivated on about 163.1 million hectares area with total production of 722.56 million tonnes with average productivity of 4.4 tonnes/ha at world level (Anonymous 2012). India is the world‟s second largest rice producer and consumer next to China. Total area under rice in India was 42.56 million hectares with annual production of 104.32 million tonnes during 2012 (Anonymous, 2012). The major rice growing districts in Maharashtra are Thane, Raigad, Ratnagiri, and Sindhudurg along with the west coast and Bhandara and Chandrapur in the eastern parts of the states. Rice is also grown in minor areas of Tuljapur, Parbhani, Western Ghat of Pune, Satara, and Kolhapur. 52 In Maharashtra, area under rice is 15.18 lakh ha with 26.88 lakh tones production. Average productivity of rice is 2.13 tones/ha in India and 1.68 tones/ha in Maharashtra, which are far below the world‟s average of 3.7 tones/ha. In Konkan, rice is cultivated over an area of 4.20 lakh hectares with an annual production of about 10.07 lakh tones with average productivity of 2.40 tones/ha (Anonymous, 2014). The main reasons for low productivity in Konkan are untimely/delayed transplanting, low plant population per unit area, broadcast application of fertilizers in imbalanced proportion, poor water and weed management practices etc. During green revolution period in latter part of the last century, high yielding varieties (HYVs) of rice and wheat responsive to fertilizers and irrigation, were developed besides enhancing crop productivity, have brought up with the problems of weeds to the fore front. For ever increasing human population, need in present Era requires greater food grain production with minimum cost. Although it should of affordable to the consumers and profitable to the farmers with emphasis on conservation of natural resources which has been the prime concern in agriculture therefore, it is essential to spell check sustainable agronomical practices that are economically viable, practically feasible and environmentally sound. Direct seeded rice is an ancient practice of rice cultivation in India particularly in rainfed areas where farmers totally eliminate costlier practices like raising seedlings and transplanting them in another puddled field as practiced in high rainfall regions of tropics. However ancient practices like Rab cultivation, seedlings are raised separately, and transplant in the puddled field. Rice in Konkan is being grown mostly as puddled transplanted crop. This method of cultivation involves labour intensive practices like traditional ‘Rab’, raising seedlings, uprooting and transplanting them in puddled fields. The term ‘Rab locally called Bhajavani/Bhajnaval is a traditional practice of heating surface area of nursery soil for raising seedlings of rice and hill millets by burning valuable organics arranged one over the other viz., dry 53 dung cakes, tree/shrub loppings, paddy straw, fodder grasses, leaf litter collected from distant forest areas and road side tree avenues which is sprinkled with dung slurry and finally a thin layer of silt rich in partially decomposed organic matter (Gawar) is uniformly spread over for making burning process slow and effective for destroying weed seeds, their vegetative propgules, besides soil borne insects and pathogens. The productivity and sustainability of rice-based systems are threatened because of (i) the inefficient use of inputs (fertilizer, water, labour); (ii) increasing scarcity of resources, especially water and labour; (iii) changing climate; (iv) the emerging energy crises and rising fuel prices; (v) the rising cost of cultivation; and (vi) emerging socio-economic changes such as urbanization, migration of labour, preference of non-agricultural work, concern about farm-related pollution. Puddling benefits rice by reducing water percolation losses, controlling weeds, facilitating easy seedling establishment, and creating anaerobic conditions to enhance nutrient availability. But repeated puddling adversely affect soil physical properties by destroying soil aggregates, reducing permeability in subsurface layers and forming hard-pans at shallow depths, all of which can negatively affect the following non-rice upland crop in rotation. Moreover, puddling and transplanting require large amount of water and labour, both of which are becoming increasingly scarce and expensive, making rice production less profitable. Also, the drudgery involved in transplanting- a job largely done by women- is of serious concern. All these factors demand a major shift from puddled-transplanted rice production to direct seeding of rice in irrigated areas (Virender Kumar and Ladha, 2011). Direct sowing in the form of drilling is a quicker, easier and economical method which needs specific seed rate for optimum plant population taking into consideration local agro-ecological conditions. Many a times when manually operated seed drill is used for sowing, initial plant population per unit area is generally more with less scope for tillering and smaller panicle size resulting in poor productivity. By using drum seeder 54 optimum plant population can be maintained. However, the weed infestation is the main problem in case of direct seeded rice. This is because weed and crop seeds germinate at the same time resulting in greater competition for space, light, nutrients and moisture from early stage of crop growth which brings down the yield drastically. Increased industrialization coupled with increased wage rates and changed psychology of rural youths for white collared jobs has not only reduced availability of farm labours but also increased cost of production thus making cultivation of seasonal crops to be uneconomical propositions. Often farmers need to sustain economic losses while growing crops like rice by following traditional practices of rice cultivation in this region. Therefore, possibility of growing direct seeded rice in Konkan is need of the present era. Accordingly many farmers and research workers have started work for developing technology of growing direct seeded rice. Direct sowing of rice is quicker, easier and economical one, but the infestation of weeds in such crop is the main problem. Weed pressure is often two to three times more in direct seeded rice as compared to transplanted one. The yield losses due to weeds range from 36 per cent in case of transplanted rice and as high as 84 per cent in case of direct sown rice (Ravichandran, 1991). Research has been shown that, in the absence of effective weed control options, yield losses are greater in direct seeded rice than in transplanted rice (Baltazar and De Datta, 1992; Rao et al. 2007). Weeds are more problematic in direct seeded rice than in transplanted rice because (1) emerging seedlings are less competitive with concurrently emerging weeds and (2) the initial flush of weeds is not controlled by flooding in wet and dry direct seeded rice (Rao et al. 2007). However, Pillai and Rao, 1974 reported the extent of yield reduction due to infestation of weeds to be 15-20 per cent under transplanted system and 30-35 per cent under direct seeded system. Out of the several factors, weeds form a serious negative factor in crop production and are responsible for marked losses in crop yields. Weeds grow faster than the crop plants and thus absorb the available nutrients earlier, 55