Tamil Nadu Agricultural University Research Articles

Impact of Selected Plant Growth Regulators on Rooting Response of Stem Cuttings of Psidium guajava L.

Guava can be propagated vegetatively through layering, cutting and grafting, in addition to seeds. Among the propagation techniques, cuttings have gained popularity because they produce results in a shorted span of time. Rooting is an essential step in the propagation of guava through cuttings. Nowadays, the most popular technique for growing cuttings in a misty environment is the use of plant growth regulators, especially auxins such as Indole-3-Butyric Acid (IBA) and Naphthalene Acetic Acid (NAA) that promote root growth. The present study was undertaken to assess the influence of plant growth regulators on the rooting of diverse stem cuttings from guava cv. Arka Kiran under mist chamber conditions at the Horticultural College and Research Institute, Tamil Nadu Agricultural University, Coimbatore, Tamil Nadu. Two plant growth regulators, IBA and NAA were employed at various concentrations. These regulators were applied to single-node cuttings with one leaf, double node cuttings with two leaves, and herbaceous cuttings. The highest rooting percentage (55.10%), the duration for bud sprouting (21.13 days), and number of leaves (4.83) were observed in single-node cuttings treated with IBA at a concentration of 3000 ppm concentration. Single-node cuttings treated with IBA at 3000 ppm exhibited superior rooting and sprouting performance compared to Naphthalene Acetic Acid (NAA). Among the three stem cuttings, single-node cuttings with one leaf proved to be the most effective for rapid multiplication.

Stability analysis in rice landraces grown under dry Direct seeded condition

In the present study the genotype x environment interaction and stability performances of 15 rice landraces in Rabi season during 2017-18 to 2021-22 at Agricultural Research Station, Tamil Nadu Agricultural University, Tamil Nadu, India were evaluated. Eberhart - Russel model was used for stability analysis in rice. In this model, genotype mean across environments, regression of genotype on environmental index and function of the squared deviation from the regression were determined. Mean sum of squares against environment source of variation as well as linear component of environment were significant for all the studied characters suggesting a presence of variation among the environments tested. The linear component of genotype x environment interaction was also found significant for all the traits studied which indicated presence of significant differences between the genotypes. The landraces Kallurundaikar and Kattanur responded favourably to better environments but gave poor yield in an unfavourable environment. Hence, they are suitable for favourable environments. Sivappuchithiraikar and Mysore malli recorded the highest grain yield with bi value closer to unity and non-significant deviation from regression. They were reported as stable genotypes and recommended for cultivation in southern districts of Tamil Nadu. Bangladesh J. Bot. 52(4): 941-948, 2023 (December)

Studies on Castor and Nutri Cereals Based Intercropping Systems on Yield and Oil Content of Castor

A field experiment was conducted during summer season of 2022 at Tamil Nadu Agricultural University, Coimbatore to study the castor and nutri cereals based intercropping systems on yield and oil content of castor. The experiment was laid out in randomize block design comprises of thirteen treatments and three replications. The experiment results revealed that nutri cereals intercropping system and spacing between the castor row have no significant difference on the oil content of the castor. The highest castor seed yield (2098 kg ha-¹) was recorded in sole castor which was found at par with paired row castor + proso millet (2:4) and paired row castor + foxtail millet (2:4) (2003 and 1914 kg ha-1 respectively). Highest castor equivalent yield of 2647 kg ha-1 was recorded in paired row of castor + foxtail millet (2:4) and it was at par with paired row of castor + proso millet (2:4) (2604 kg ha-1) than sole castor (2098 kg ha-1). From this study, it is to be concluded that proso millet and foxtail millet are suitable nutri cereals for intercropping in castor under paired row system to increase monetary yield.

Evaluation of Blackgram Genotypes for their Drought Tolerance at Seedling and Vegetative Phase

Aim: To screen and identify blackgram genotypes for drought tolerance at seedlings and vegetative stage.
 Study Design: Completely randomized complete block design.
 Place of Study: National Pulses Research Centre (NPRC), Tamil Nadu Agricultural University, Vamban, Pudukkottai District.
 Methodology: Laboratory experiments was conducted at NPRC, Vamban. Twenty-Five blackgram varieties were used for this study. For screening at seedling stage, the treatments were T1 - Control – Water (0 Mpa) and T2 - PEG 6000 induced drought stress (-0.5 MPa). Blackgram seeds were germinated in water and PEG 6000 solution (-0.5 MPa). On the eighth day various seedling growth indices were recorded. For pot culture experiments, the two treatments were imposed T1 – Control and T2 – Drought stress (50% Field capacity) after the appearance of two trifoliate leaves by gravimetric approach. The stress was imposed for five days. At the end of fifth day, growth parameters, relative water content and leaf chlorophyll content was recorded. Two-way ANOVA was used to analyze the data.
 Results: In blackgram, drought stress at seedling stage affects the seedling germination, establishment and its growth indices. At vegetative stage, drought stress negatively affects the plant growth, leaf area, leaf relative water content and chlorophyll content. Among the blackgram genotypes screened, the genotypes VBG 11031 and VBG 1711 were found to be tolerant to PEG 6000 induced drought stress at seedling stage. At vegetative stage, the genotypes VBG 11062, VBG 11024 and VBG 1725 were tolerant to drought stress at vegetative stage.
 Conclusion: Present study concluded that the blackgram genotypes VBG 11031, VBG 1711, VBG 11062, VBG 11024 and VBG 1725 were found to be tolerant to drought stress at seedling and vegetative stage.

Growth and Productivity of Castor as Influenced by Millet Based Intercropping Systems

A field experiment was conducted during summer season of 2022 at Tamil Nadu Agricultural University, Coimbatore to study the influence of millet based intercropping systems on growth and productivity of castor under irrigated situation. The experiment was laid out in randomized block design and replicated thrice. The treatment consist of nine cropping systems viz., castor + foxtail millet (1:3), castor + proso millet (1:3), castor + little millet (1:3), castor + kodo millet (1:3), paired row castor + foxtail millet (2:4), paired row castor + proso millet (2:4), paired row castor + little millet (2:4), paired row castor + kodo millet (2:4), sole castor. Experimental results revealed that the different millet based cropping systems significantly influenced growth and productivity of castor. Sole castor was recorded the highest growth, yield parameters and seed yield (20.98 q/ha). Among the millet based intercropping systems, maximum values of growth parameters viz., plant height (170.20 cm), number of branches/plant (7.90), stem girth (8.70 cm) and dry matter production (29.83 q/ha) were recorded in the paired row castor + proso millet (2:4) and it was on par with paired row castor + foxtail millet (2:4). Similarly, yield and yield attributing characters viz., number of spike/plant (28.2), number of capsule/ spike (55.8), highest length of primary branch (40.1 cm) and seed yield (20.03 q/ha) was obtained in paired row castor + proso millet (2:4) and it was comparable paired row castor + foxtail millet (2:4). The economic study revealed that the higher net return and benefit cost ratio was obtained from paired row castor + foxtail millet (2:4) (₹. 74,842.00 and 2.30) and paired row castor + proso millet (2:4) ((₹. 72,702.00 and 2.26). From this study, it was concluded that proso millet and foxtail millet were indentified to be compatible intercrops with castor for improved productivity.

Phenology, phyllochron and productivity of sorghum in response to varying growing environments and nitrogen levels in the semiarid irrigated condition

Climate change is likely to affect agricultural production in many parts of the world. Sorghum is the stable food crop in semiarid areas, and climate change has significant adverse effects on sorghum yields. The optimum time of sowing is one of the important technologies that allow the crop to better utilise natural resources by the crop to maximise productivity. For optimizing the sowing time, the field investigation was carried out in Tamil Nadu Agricultural University, Coimbatore, under summer irrigated conditions in 2022. The experiment was laid out in a split-plot design with three replications. The main plot consists of five dates of sowing and the subplot includes different nitrogen levels. The results revealed that advanced sowing (first fortnight of April) reduced the yield by 13.73% and delayed sowing (second fortnight of May) recorded the maximum yield (4230.3kg ha-1) with higher phyllochron values. GDD manifested a significant negative relationship with a high correlation coefficient (r) value of -0.98** (p = 0.01) for days to anthesis, -0.98** (p = 0.01) for days to physiological maturity and -0.88* (p = 0.05) for phyllochron. Average temperature exhibited a significant negative correlation with days to anthesis (-0.75*), physiological maturity (-0.97**) and phyllochron (-0.89*). The best-fit regression model showed that a GDD-based model could better predict the phenology of sorghum compared to an average temperature-based model. The study indicated that understanding sorghum's phenological response and productivity level under varied dates of sowing and the nitrogen levels in semiarid environments can help determine the appropriate sowing time and optimum nitrogen level for achieving better yield in summer-irrigated sorghum.

Principal Component Analysis for Quality Traits in Indigenous Moringa (Moringa oleifera L.) Germplasm Lines

The present investigation was carried out at Department of Vegetable Crops, Horticultural College and Research Institute (HC&RI), Tamil Nadu Agricultural University, Periyakulam during 2016 -2017 with twenty genotypes in order to study the genetic diversity for different Quality characters of Moringa by principal component analysis. In this study, out of five principal components (PC), only three components exhibited eigenvalues greater than 0.5 and accounted for 84.12% variability. The PC1 accounted for the highest variability (52.53% of) the total variability, followed by PC2 (17.66%) then PC3 with 13.93%. Thus the results of the principal component analysis revealed, wide genetic variability exists in this Moringa genotype accessions.

Evaluation of different tillage and intercropping systems in castor under rainfed conditions

The field experiments were conducted in 2020-21 and 2021-22 at Tapioca and Castor Research Station, Tamil Nadu Agricultural University, Yethapur. The pooled result of the two-year study of different tillage practices in castor based legume intercropping systems in rainfed, there was no significant difference among tillage practices relevant to growth, yield attributing characters, seed yield and biomass yield, numerically higher values were registered under conventional tillage practices over minimum tillage. The higher seed yield of both base (1152 kg/ha) and inter crop (481 kg/ha) were recorded in conventional tillage practices over minimum tillage. With respect to inter cropping, higher base crop (castor) yield of 1058 kg/ha was recorded under castor + groundnut inter cropping system which was observed to be on par with sole castor (1020 kg/ha) and castor + greengram (907 kg/ha). The highest. Moreover, the maximum benefit-cost ratio was recorded in castor + groundnut (1:3) intercropping, over solecastor cropping.

Assessment of Ginger Genotypes under Coconut Ecosystem for Quantitative and Qualitative Traits

Ginger is one of the major spice grown in subtropical hilly regions and ultivation of ginger under coconut ecosystem is gaining popular among the farmers. Coimbatore district, Pollachi region is one of the major coconut growing belt in Tamilandu. With this view an experiment was conducted to evaluate the performance of ginger genotypes under coconut ecosystem at Coconut Research Station, Aliyar Nagar, Tamil Nadu Agricultural University, Coimbatore during 2018- 2020. . Fourteen ginger genotypes/ varieties were collected for this study. The ginger rhizomes were sown in the prepared land all cultural operations as per the TNAU recommendations were followed uniformly. Growth and yield parameters of ginger genotypes were recorded for three seasons. The date collected were pooled and analysed for statistical significance. Among the fourteen varieties of ginger, var. Athira excelled with respect to number of primary fingers (4.8), length of primary fingers (4.4 cm), diameter of primary finger (2.5 cm), number of secondary finger (5.7), days to maturity (248), TSS (10.40 Brix), acidity (0.41%), Dry matter content (18.9%), fibre content (9.6%), Essential oil content (11.2 mg/g of dry ginger), Gingerol content (19.6 mg/g of dry ginger ) and lowest incidence of soft rot (11.4 %). On the basis of good performance Athira is adjudged as the suitable ginger genotype under coconut shade condition of this region.

Study To Evolve Technology For Controlling Binding Weeds In Grown-Up Sugarcane Crop

Field investigations were carried out at Sugarcane Research Station, Cuddalore Tamil Nadu Agricultural University, to evolve technology for controlling binding weeds in grown-up sugarcane crops during 2015-18. The experiments were laid out in Randomized Block Design with three replications and the sugarcane variety tested wasCoC(SC)24. The treatments constituted of T1 – PE. atrazine @ 1.0 kg/ha and Po.Emetribuzin 0.75 kg/ha @ 60 DAP, T2 – PE atrazine 1.0 kg/ha and Po.E 2,4D Na salt 1.25kg/ha @ 60 DAP, T3 – P.E atrazine 1.0 kg/ha followed by weeding and earthing up on 75 DAP, T4 – Mechanical weeding by power tiller (45, 90 and 120 DAP), T5 – Intercropping of sun hemp and its incorporation as insitu on 60 DAP, T6 – Detrashing and mulching at 150th&210th DAP, and T7 – hand weeding and manual removal of weeds on 45, 90 and 120th days and T8 – Control. Based on the performance of herbicides, the Pre-emergence application of atrazine @ 1.0 kg a.i/ha followed bypost-emergence application of metribuzin @ 0.75 kg/ha on 60 days after planting was the best treatment for controlling weeds in grown-up sugarcane and also the yield attributes increased in sugarcane compared to control. The critical period of weed crop competition in sugarcane ranged between 27 and 50 days (Srivastava et al., 2003). Sugar yield as well as juice quality greatly affected by the application of weed control treatments. The presence of weeds in the sugarcane fields and no control has also led to a decrease in sugar yield (Roshan et al., 2006.; Patel et al., 2007; Kanchan, 2009) in proportion of sucrose, purity and brix ( Bahadar et al., 2004; Annual Report, 2012) . Generally, the increase in by weed growth one kilogram corresponds to a reduction in one kilogram of the crop. The reduction in cane yield due to weeds ranged from 40-60% (Kadam et al., 2011).

Prevalence, Cultural And Morphological Characterization Of Fusarium Verticillioides Associated With Ear Rot Of Maize

Sorghum shoot fly, Atherigona soccata (Rondani) is an important pest of sorghum distributed in almost all sorghum growing areas of India, attacking the crop at the seedling stage wherein the absence of appropriate management measures may result in heavy yield loss and host plant resistance is a major component in managing this pest. Utilization of resistance as a control strategy has very much practical relevance and hence identification of resistant sources for shootfly through morphological and physicochemical characteristics was carried out in pre-release sorghum genotypes of Tamil Nadu Agricultural University. Leaf glossiness, trichome density, trichome length, trichome width, and seedling vigor were associated with resistance and had a major bearing on the expression of resistance to shoot fly. Among the genotypes tested, TNS 671 and TNS 665 showed better performance in terms of dead heart, percentage of plants with eggs, and recovery resistance compared to others which were then subjected to biochemical estimation and GCMS analysis. Leaf biochemical characters viz., total phenol, cellulose, total amino acids, silica, tannin, and lignin were found to be negatively correlated and total sugar positively correlated with resistance. GC-MSanalysis of the sorghum genotypes revealedthe presence of compounds, viz., carboxylic acids, heptadecene, and hentriacontane only in the resistant entry, IS18551. An interesting finding of this study was the presence of hentriacontanein resistant cultivar, IS18551 which is reported to have kairomonal activity. The characters associated with resistance or susceptibility can be used in further resistant breeding programmes.

Morphological And Biochemical Resistance In Sorghum Genotypes Against Sorghum Shoot Fly, Atherigona Soccata (Rondani) (Muscidae: Diptera)

Sorghum shoot fly, Atherigona soccata (Rondani) is an important pest of sorghum distributed in almost all sorghum growing areas of India, attacking the crop at the seedling stage wherein the absence of appropriate management measures may result in heavy yield loss and host plant resistance is a major component in managing this pest. Utilization of resistance as a control strategy has very much practical relevance and hence identification of resistant sources for shootfly through morphological and physicochemical characteristics was carried out in pre-release sorghum genotypes of Tamil Nadu Agricultural University. Leaf glossiness, trichome density, trichome length, trichome width, and seedling vigor were associated with resistance and had a major bearing on the expression of resistance to shoot fly. Among the genotypes tested, TNS 671 and TNS 665 showed better performance in terms of dead heart, percentage of plants with eggs, and recovery resistance compared to others which were then subjected to biochemical estimation and GCMS analysis. Leaf biochemical characters viz., total phenol, cellulose, total amino acids, silica, tannin, and lignin were found to be negatively correlated and total sugar positively correlated with resistance. GC-MSanalysis of the sorghum genotypes revealedthe presence of compounds, viz., carboxylic acids, heptadecene, and hentriacontane only in the resistant entry, IS18551. An interesting finding of this study was the presence of hentriacontanein resistant cultivar, IS18551 which is reported to have kairomonal activity. The characters associated with resistance or susceptibility can be used in further resistant breeding programmes.

Seed pelleting technique for mechanized sowing in green gram [Vigna radiata (L.) R. Wilczek

Background: Now-a-days, use of machines is becoming important due to shortage of labour for field operations. One such case is seed drill sowing which warranted enough seed size for easy sowing. Pelleting of seed is one of the techniques through which the size of the seed can be increased thereby it can be sown easily by seed drill. Green gram is one of the important pulses which needs pelleting technique for mechanized sowing. Methods: The experiments on standardization of seed pelleting technique and evaluating under field conditions were conducted in the Department of Seed Science and Technology, Seed Centre, Tamil Nadu Agricultural University, Coimbatore, India during 2019-2022. The green gram var. CO 8 seeds were primed and pelleted with TNAU pelleting mixture. Then, the pelleted seeds were sown by pneumatic seed drill and evaluated for its field performance. Result: The results showed that the green gram seeds primed with MnSO4 @ 0.5% and pelleted with 7 layers of TNAU pelleting mixture along with imidacloprid 70 WS @ 7 g/kg have recorded increased seedling vigour without affecting the seed germination. Also, the seeds sown by seed drill have recorded with better plant growth traits and higher yield. Also, single seed placement was achieved by seed drill sowing and about 25% seeds can be saved.

Evaluation of Storage Techniques to Improve the Seed Longevity of Horsegram

Horsegram (Macrotyloma uniflorum) is a robust, drought-resistant crop that is valued for its high protein content and is a significant food source in many parts of the world. Horsegram seeds must be stored properly to preserve their freshness, nutritional value, and viability for future planting. In this article an investigation was carried out to evaluate the suitable seed treatment and packaging materials for maintaining the shelf life of horsegram seeds during storage. The laboratory experiment was carried out at Department of Seed Science and Technology, Agricultural College and Research Institute, Tamil Nadu Agricultural University, Madurai, India. The graded seeds of horsegram were treated with different botanicals (Neem seed kernel powder @ 5g/kg & Pungam leaf powder @ 5g/kg), herbal oil (Neem oil @ 5ml/kg) and chemical (Malathion @ 5g/kg) and packed in cloth and super grain bags which was kept under ambient condition. The physical, physiological and biochemical parameters were assessed from the stored seed samples. Horsegram seeds dusted with malathion at 5 g/kg and then packed in a super grain bag have better germination (94%), root length (18.33 cm), shoot length (9.10 cm), DMP (0.165 g seedlings-10), vigour index I and II (2551 and 16.2), and also biochemical parameters like the lowest electrical conductivity (0.121 dSm-1), highest enzyme activity like dehydrogenase (0.521) and catalase (0.213 units g-1) and protein level (19.21%) was also high in malathion (5 g/kg) treated seeds packed in a super grain bag after storage for 8 months.

Evaluation of Performance of Turmeric (Curcuma longa L.) Varieties in Dharmapuri District of Tamil Nadu, India

Turmeric is an important spice crop cultivated in various states of India and Tamil Nadu is one of the leading producers of Turmeric. The productivity of Turmeric in Tamil Nadu was 3.80 MT/ha (cured rhizome yield) which is lower than the national productivity. Though there are various factors affecting productivity, choice of varieties was one of the important factors among them. On farm trials were conducted to study the performance of Turmeric varieties viz. BSR 1, BSR 2, CO 2, Allepey Supreme, PTS 10 and Roma at Krishi Vigyan Kendra, Papparapatty of Dharmapuri district. The experiment was conducted in randomized block design with three replications. The crop management practices are carried out as per Crop Production Guide 2020 of Tamil Nadu Agricultural University, Coimbatore recommendation. The yield data revealed that there was significant variation among the turmeric varieties in various growth and yield determining parameters. Among the varieties CO 2 performed better than the other varieties with highest yield per plant (468.99 g), cured rhizome yield per hectare (6.82 tonnes/ha) followed by BSR 2. The results of the study show that CO 2 performed better in Dharmapuri district when compared to other varieties and hence can be preferably recommended to the farmers for better yield. The yield attributing factors viz. plant height, leaf size, weight of mother rhizome, weight and number of primary and secondary fingers are positively correlated with the yield per plant and hence can be used as criteria for varietal selection.

Optimizing Pre-emergence Herbicide Oxyfluorfen Dose based on Its Sorption and Desorption for Effective Weed Management under Different Soil Types

Background: Adsorption and subsequent release of pre-emergence herbicide into the soil solution decides the herbicide availability to kill the weeds. Herbicides applied on clay or organic rich soil type, absorb more results in lowering its availability in soil solution become sub lethal to kill the weeds, whereas sandy soil adsorb less and desorb more, sometime it increases the herbicide concentration to toxic level to crop. Effective weed control could be achieved by studying the variability of soil and deciding the dose based on the sorption and desorption properties of the soil. Methods: With this information on the background a laboratory experiment was conducted at the Department of Agronomy, Agricultural College and Research Institute, Tamil Nadu Agricultural University, Madurai, India during 2021 to study the optimum level of oxyflourfen concentration in soil solution required to kill the weeds effectively. The study on sorption and desorption was carried out with pre-emergence herbicide oxyflourfen with five different concentrations in five different soil types. Result: The highest sorption of 98.53 per cent was observed with clayey soils followed by sandy clay loam soils with high organic matter content (96.97 per cent). The lowest sorption (77.96 per cent) was recorded with sandy loam soils. The highest desorption of 57.44 per cent was recorded with sandy loam soil and the lowest desorption percentage (13.18 per cent) was obtained with sandy clay loam soil with higher organic matter. Based on the analytical results of sorption and desorption, oxyflourfen dose was optimized as 0.53 kg ha-1 for sandy clay loam soils with high organic matter, 0.34 kg ha-1 for clay soil, 0.29 kg ha-1 for sandy clay, 0.21 kg ha-1 for sandy clay loam soil and 0.12 kg ha-1 for sandy loam soils. In conclusion, the clay soil required more quantity of oxyflourfen compared to other types of soil for effective management of weeds under irrigated condition.

Per se performance of elite coconut genotypes and hybrids for economic quality traits and oil yield

The present study was conducted at Coconut Research Station, Aliyarnagar Tamil Nadu state of India. The experimental trees comprised of five tall coconut genotypes viz., IC 610370, IC 610371, IC 610372, IC 610374 and IC 610379 West Coast Tall (Check), and the hybrids viz., Chowghat Orange Dwarf x Aliyar 1 (COD x ALR1), Chowghat Orange Dwarf x West Coast Tall (COD x WCT), Aliyar 1 x Malayan Green Dwarf (ALR1 x MGD), Malayan Green Dwarf x Aliyar 1 (MGD x ALR), Kenthali Dwarf x Aliyar 1 (KTD x ALR1) and Veppankulam Hybrid Coconut VHC 2 (Check hybrid - released from Veppankulam Coconut Research Station, Tamil Nadu Agricultural University, Tamil Nadu, India). Coconut palms of uniform size were taken from the chosen genotypes and hybrids for recording the observation. All the coconut genotypes and hybrids showed variation in yield, nut characters, and quality traits. The results of the present study revealed that the genotype IC 610370 and the hybrid COD x WCT recorded maximum values for all the recorded traits. This was followed by the genotype IC 610371 and the hybrid COD x ALR1.

Assessing the Performance of Latest Greengram Varieties under Improved production Packages in Thiruppur, Tamil Nadu, India

On Farm Testing (OFT) in Mungbean Yellow Mosaic Virus (MYMV) resistant and high yielding greengram varieties was conducted by Krishi Vigyan Kendra, Tamil Nadu Agricultural University, Tirupur in farmers field during kharif 2020. Totally 15 farmers each with one acre were selected in three villages of Pongalur Block in Tirupur district of Tamil Nadu. Critical input viz., seeds of greengram varieties CO 8 and DGG 1 were distributed to the farmers and the varietal performance were assessed along with the existing variety under cultivation VBN 2. The plant physiological parameters viz., plant height, number of nodules / plant and yield attributing parameters such as number of pods / plants, number of branches/plant, Mung bean Yellow Mosaic Virus (MYMV) disease incidence (%), yield (q ha-1) and B:C ratio were recorded. The results revealed that, among the three varieties, Greengram CO 8 was recorded more number of pods (42) and minimum incidence of Mungbean Yellow Mosaic Virus (MYMV) disease incidence of 3.2 per cent resulting in the highest yield of 9.5 q ha-1 followed by DDG 1 with 34 pods/plant, MYMV disease incidence of 7.3 per cent and yield of 8.4 q ha-1 compared to the existing variety VBN 2, which recorded the lowest number of pods (31 Nos.), yield (7.6 q ha-1) with the highest MYMV disease incidence (12.5%). The highest B:C ratio was recorded in greengram variety CO 8 (2.92) which was followed by DDG 1 (2.58). It was concluded that, farmers of Tirupur district in Tamil Nadu were satisfied with cultivation of greengram CO 8 variety due to the lowest disease incidence, higher yield and Benefit Cost Ratio.

Effect of Herbigation on Weed Control and Yield of Drip Irrigated Cotton

A field experiment was conducted during Summer, 2023 at Anbil Dharmalingam Agricultural College and Research Institute, Tamil Nadu Agricultural University, Tiruchirappalli to study the effect of herbigation on weed control and yield of drip irrigated cotton. The experiment was laid out in randomized block design with nine treatments and replicated thrice. The treatments consisted of herbigation of pre emergence (PE) herbicides (Pendimethalin 1.0 kg ha-1 and Oxyfluorfen 0.2 kg ha-1) combined with hand weeding at 45 DAS or manual spray or herbigation of post emergence (PoE) herbicide (Pyrithiobac Sodium + Quizalofop Ethyl 75 g ha-1 on 25 DAS) compared with recommended practice of manual spray of PE pendimethalin 1.0 kg ha-1 + HW at 45 DAS, HW twice on 20 and 40 DAS and unweeded control. The results revealed that among the different weed management practices manual spray of PE pendimethalin 1.0 kg ha-1 + HW at 45 DAS registered significantly lower total weed density (12.63 m-2), total weed dry weight (8.23 g m-2) and higher weed control efficiency (77%) at 20 DAS. This was followed by herbigation of PE pendimethalin 1.0 kg ha-1 + manual spray of PoE pyrithiobac sodium + quizalofop ethyl 75 g ha-1 on 25 DAS. Among the herbigation treatments, herbigation of PE pendimethalin 1.0 kg ha-1 + manual spray of PoE pyrithiobac sodium + quizalofop ethyl 75 g ha-1 on 25 DAS obtained lower total weed density (12.13 m-2), total weed dry weight (9.19 g m-2) and higher WCE (86%) at 40 DAS. This was followed by herbigation of PE oxyfluorfen 0.2 kg ha-1 + manual spray of PoE pyrithiobac sodium + quizalofop ethyl 75 g ha-1 on 25 DAS. At 60 DAS, application of manual spray of PE pendimethalin 1.0 kg ha-1 + HW at 45 DAS recorded lower total weed density (18.07 m-2), total weed dry weight (16.03 g m-2) and higher weed control efficiency (85%). However, this was comparable with herbigation of PE pendimethalin 1.0 kg ha-1 + manual spray of PoE pyrithiobac sodium + quizalofop ethyl 75 g ha-1 on 25 DAS and HW on 20 and 40 DAS. The highest seed cotton yield (2109 kg ha-1) was obtained with manual spray of PE pendimethalin 1.0 kg ha-1 + HW at 45 DAS and it was on par with herbigation of PE pendimethalin 1.0 kg ha-1 + manual spray of PoE pyrithiobac sodium + quizalofop ethyl 75 g ha-1 on 25 DAS and HW on 20 and 40 DAS. Hence, considering the labour scarcity, herbigation of PE pendimethalin1.0 kg ha-1 on 3 DAS followed by manual spray of PoE pyrithiobac sodium + quizalofop ethyl 75 g ha-1 on 25 DAS could be recommended for better weed control in drip irrigated cotton.

Impact of Training on Modern Machineries and Improved Agricultural Technologies towards Cognitive Assessment of Farmers

In the era of fast changing technology, training has become an integrated part of investment for accelerating transfer of technology to people of all walks of life. The well-established network of organizations spread over the length and breadth of the country. The budget spent on training has tremendously increased over the past few years. with this background the study under taken at Trichy district, Tamil Nadu state of a country India by employing purposive sampling procedure. Agricultural Engineering College & Research Institute, Kumulur is one of the constituent colleges of Tamil Nadu Agricultural University located in Trichy. It is a pioneer institute in Tamil Nadu doing research on Agricultural Engineering technologies and Machinery. It is being chosen by the Tamil Nadu Govt. for state level capacity development trainings of farmers under the Agricultural Technology Management Agency and Agrl. Engineering Department (AED). Using simple random sampling procedure 10 farmers (trainees) were selected from 18 Districts of Tamil Nadu who were visited the institution during the study period. (180 sample size). The major objectives, as study of socioeconomic profile and knowledge assessment during pre and post training on Farm Machineries, Bio-energy, Agricultural Processing, Soil and Water Conservation, Drip irrigation and improved Agricultural sciences. Among 180 respondents, Majority of them were old age group (38.89 %) studied primary education (30.00 %) equally spread in marginal and small land holdings (around 75 %), possessed high level of farming experience (38.89 %) had medium level of extension agency contact (47.78 %), possessed medium level of Information seeking behaviour (53.89 %) with a medium level of Innovativeness (42.78 %). Knowledge test was assessed prior to training, among 180 respondents, Majority of farmers belonged to the medium level of knowledge category on all six categories and the after training knowledge test showed that the respondents belonged to low level were distributed in medium to high level of knowledge category and the medium level was elevated to high level category. The alternate hypothesis (H1)was proved through ‘ t’ test that there was a significant difference prevailed in the knowledge level of the respondents acquired through the trainings conducted on the recently developed Agrl. Technologies and modern machineries.