Effect of rainfall on growth and yield of rice in Konkan coast

In this Study, relationship between rainfall and rice yield has been investigated in Ratnagiri and Thane districts of Maharashtra using 37 year's (1951.1987) data. Weekly water balance has been worked out in developing a yield index and its association with yield examined. Planting rates have been calculated assuming two categories of empirical rainfall accumulations of 450 and 500 mm. The yields were correlated with rainfall during selected growth phases, total rainfall, the yield index and the technological trend. Effects of late or early onset on yield has also been examined. It appears that 450 mm rainfall accumulation from Ist June gives a ~reasonably accurate indication of transplanting paddy in Konkan. Technology seems.. to have much influence on the paddy yield. Results also reveal that rainfall during early growth phases is significantly related to the yield the date of planting was not found to/have a determining influence on the yield.

Evaluation of Different Land Preparation Techniques for Preparing Medium Textured Soil in Rice Production under Agro-Ecological Conditions of Sheikhupura-Pakistan

Tillage is an important factor affecting different soil properties and crop yields. Tillage relates to applying forces to soil using different implements for preparation of a proper seed bed. For rice crop, land preparation is a rigorous and time consuming operation that needs special attention for preparing a puddled soil condition to transplant the weak and tender rice seedlings. A field experiment was established under agro-ecological conditions of Sheikhupura to evaluate different land preparation techniques during fall in 2017 and 2018 years. The experiment was performed at Adaptive Research Farm Sheikhupura. It was laid out in randomized complete block design (RCBD) with four different land preparation techniques including T1= Cultivator (4 times) + Planking (2 times) (Farmer’s Practice), T2=MB plough (1 time) + Disc Harrow (1 time) + Planking (2 Times), T3=MB plough (1 time) + Cultivator (2 times) + Planking (2 Times) and T4= Rotavator (1 time) + Disc Harrow (1 time) + Planking (2 Times), each treatment replicated thrice during both the years. All the other agronomic and crop husbandry operations were kept uniform throughout the growing season every year. The results revealed that preparing land with MB plough (1 time), Disc Harrow (1 time) and Planking (2 times) is the best land preparation method can increase the paddy yield 13.5-17.5% as compared to the traditional method practised by the farmers. Moreover, highest plant height (134.00 cm and 132.00 cm), number of tillers (224 and 220 m-2), number of grains per spike (130 and 116) and 1000-grain weight (23.0 and 22.0 g) respectively during Kharif-18 and Kharif-19 was also recorded in the same treatment. So, preparation of land for paddy in agro-ecological conditions of Sheikhupura using MB plough (1 time), Disc Harrow (1 time) and Planking (2 times) can significantly enhance the paddy yield.

Weed-Free Durations and Fertilization Regimes Boost Nutrient Uptake and Paddy Yield of Direct-Seeded Fine Rice (Oryza sativa L.)

Under the changing climate, fertilization regimes and weed infestation management in aromatic direct-seeded fine rice (DSR) remain vital for curbing environmental hazards and ensuring food security. A multi-year field study was undertaken to appraise the influence of fertilization techniques and weed-free periods on weed dynamics, nutrient uptake and paddy yield in a semi-arid environment. Treatments included two fertilization methods (broadcasting and side placement) and five weed-free durations (20, 30, 40, 50 post-seeding days, DAS) along with a weed-free crop for a whole season. Weed competition for a season-long crop (weedy check) was maintained for each fertilizer application method. Our results revealed that the side placement of fertilizers resulted in a significantly lower weed density and biomass, even under season-long weed competition. The highest paddy yield was recorded for a crop without weeds, while weed-free duration of up to 50 DAS followed it. The uptake of nitrogen (N), phosphorus (P) and potassium (K) for a weed-free duration of up to 50 DAS were only 19%, 9% and 8%, respectively, as compared to the weedy check. The uptake of N, P and K by weeds in the broadcast method was 18%, 30% and 24% higher, compared to side-placed fertilizers. The period of 20–50 DAS remained critical in DSR as far as weed control was concerned. Thus, the side placement of fertilizers and controlling weeds for up to 50 days after rice sowing can be recommended for general adoption in semi-arid agro-ecological conditions.

Path Coefficient Analysis of Growth and Yield Traits of Rice (Oryza sativa L.) at Bokolori, Talata Mafara, Sudan Savanna Ecological Zone, Nigeria

In order to determine the direct and indirect effects of yield and yield components of rice, a field experiment was conducted in each of the wet seasons of 2016 and 2017 at Irrigation Research Stations of the Institute for Agricultural Research, Bokolori, Talata Mafara, in the Sudan Savanna ecological zone of Nigeria (12° 34’ N; 06° 04’E). The treatment consisted of four (4) weed management practice (Oxadiazon at 1.0 kg a.i ha-1 [pre-emergence], Orizo-plus [proponil 360 g/l + 2,4-D 200 g/l] at 2.8 kg a.i ha-1[post emergence at 3 WAS], manual weeding [at 3 and 6 WAS] and weedy check [control]); three (3) each of seeding method (Drilling, Dibbling and Broadcast) and seed rate (40 kg ha-1; 70 kg ha-1; 100 kg ha-1). The experiment was laid in a split plot design replicated three times. Weed management practice was assigned to the main plots while the combination of seeding method and seed rate to the subplots. Data were collected on plant height, leaf area, crop dry matter, tillering ability, crop growth rate, harvest index (HI), panicle length, number of grains per panicle, 1000-grain weight and paddy yield. The result indicated that, the highest individual contribution of 25.04% to paddy yield was made by dry matter followed by 1000-grain weight (8.74%), tillering ability (8.46%), leaf area (3.13%), number of grains per panicle (1.03%) and the least was from panicle length (0.83%). The contribution of these growth and yield attributes to yield suggests that, priority be given to these traits when making selection for improvement.

Correlation of yield with early seedling performance and physio-biochemical traits in Basmati rice mutants subjected to heat stress

The present study aims at deciphering the response of Basmati rice mutants to high temperature stress. The work aims to find an early screening method by correlating seedling and physiological response to yields. After rigorous screening in controlled environment (growth chamber) and field conditions over a period of four years 16 mutants’ lines were selected: HTT-18, HTT-29, HTT-31, HTT-39, HTT-51, HTT-53, HTT-74, HTT-81, HTT-92, HTT-97, HTT-98, HTT-104, HTT-114, HTT-119, HTT-132 and HTT-138. These have been tested against standards: Super Basmati and IR-64. Field trials were conducted at three locations while early seedling-stage traits and their biochemical analyses were studied in growth chamber experiments. Data of seedling traits were used to establish correlations with paddy yield under hot field conditions. The temperatures were high at two sites: Multan and Bahawalpur ranging 24-46 °C and 25-45 °C respectively), and relatively lower at NIAB field station (26-45 °C. The paddy yield was significantly correlated with early seedling-stage traits such as shoot length (0.79**), shoot fresh and dry weight (0.48* and 0.49*), and cell membrane thermo-stability (0.60**). Additionally, significant higher activities of antioxidants (SOD and APX) and lower stress indicators (MDA, esterase and TOS) were observed in the heat tolerant mutants. These mutants were classified for their heat tolerance by principle component analysis (PCA) using yield-correlated early seedling-stage and other physio-biochemical parameters. As a result, the heat tolerance classification of mutants based on PCA coincided with the yield of mutants grown under hot field conditions. The present study suggests that these seedling parameters may be used as surrogates for field performance and used in the selection of thermo-tolerant Basmati rice

Yield and Commercialisation Effects of SRI Interventions in Mngeta, Kilombero District, Tanzania

This paper discusses System of Rice Intensification (SRI) interventions and its potential effects on paddy yield and commercialisation in Mngeta division, Kilombero district in Morogoro region, Tanzania. SRI is an innovative agroecological methodology that aims to improve yields and farmers’ profits by creating the most suitable environment for the rice plant to grow. It comprises the precise set of cultivation practices specifically required for careful management of biophysical needs of the rice plant for producing high yields. To assess the effects, we compare between trained and non-trained farmers, as well as between farmers who are members of SRI associations and non-SRI members, on aspects of adoption of SRI interventions, paddy productivity and yields. In turn, the effects of SRI is evaluated in terms of its influence on rice yield per hectare and commercialisation at household level.

Trained neural network to predict paddy yield for various input parameters in Tamil Nadu, India

The major objective of the present study was to explore if Artificial Neural Network (ANN) models with back propagation could efficiently predict the rice yield under various climatic conditions; ground-specific rainfall, ground-specific weather variables and historic yield data. The back propagation algorithm will calculate each expected weight using the error rate as the activity level of a unit was altered. The errors in the model during the training phase were solved during the back-propagation. The paddy yield prediction took various parameters like rainfall, soil moisture, solar radiation, expected carbon, fertilizers, pesticides, and the long-time paddy yield recorded using Artificial Neural Networks. The R2 value on the test set was found to be 93% and it showed that the model was able to predict the paddy yield better for the given data set. The ANN model was tested with learning rates of 0.25 and 0.5. The number of hidden layers in the first layer was 50 and in the second hidden layer was 30. From this, the testing value of R square was 0.97. The observations with the ANN Model showed that i) the best result for the test set was R2 value of 0.98, ii) the two hidden layers kept with 50 neurons in the first layer and 30 neurons in the second one, iii) the learning rate was of 0.25. With all these configurations, maximum yield is possible from the paddy crop.

An Econometric Model for Nigeria’s Rice Market

A dynamic econometric model of Nigeria’s rice market was designed to serve as a base for future policy analyses. Using time-series data spanning 38 years, the model contains four structural equations representing paddy area harvested, paddy yield, per capita demand, and producer price variables. Estimates for these equations were obtained using the autoregressive distributed lag (ARDL) cointegration approach. Results of the paddy production and yield sub-models showed that paddy area harvested, and paddy yield was price inelastic. Furthermore, the paddy area harvested responded favourably to technological advancement. For the demand sub-model, estimated own price and cross-price elasticities showed that rice has an inelastic demand response, with wheat being a substitute. A series of validation tests strengthened the reliability of the model for use as an empirical framework for forecasting and analysing the effects of changes in policies such as rice import tariff reforms on production, consumption, retail price, and imports.