Effect of different salinity levels on plant growth parameters of tomato

Soil and water salinity is one of the major problems in the world for agricultural production. Tomato is one of the ten most important fruit and vegetables consumed in the world, with approximately one hundred million tonnes of fresh tomato fruit being produced worldwide every year. This research was conducted to determine the different evels of EC d S m-1 in irrigation water collected from Central Farm well water and Bore well water of Agricultural College and Research Institute, Madurai and Periyar Vaigai Command water in the year 2018 were evaluated Based on their growth and yield of tomato (PKM 1) . The results indicated that there was consistent decrease in yield with increase in salt concentration in saline irrigation water and yield and it was found that the maximum salinity tolerance is 2 d S m-1.

Effect of amount and time of incorporation of forest litter on soil physical properties

A field experiment was conducted to evaluate the effect of forest litter and its time of incorporation on soil physical properties. The study showed that plots with forest litter incorporated at 45 DBS (Days Before Sowing) had significantly higher soil moisture content as compared to those incorporated at 30 DBS after 30 and 60 DAS. However, the difference in the time of incorporation had no significant effect on soil moisture content at 90 DAS. At 30 DAS, application of forest litter @ 6 t ha-1 and 9 t ha-1 significantly increased the soil moisture content at a rate of 4.11 and 11.42 per cent, respectively over control. At 60 DAS, application of forest litter @ 3 t ha-1, 6 t ha-1 and 9 t ha-1 significantly increased the soil moisture content at the rate of 15.05, 17.26 and 25.65 per cent, respectively over control. At 90 DAS, a trend was noticed which showed that soil moisture content significantly increased at a progressive rate with each increase in the dose of forest litter application. At 90 DAS, the addition of forest litter @ 3 t ha-1, 6 t ha-1and 9 t ha-1 increased the soil moisture content @ 10.16, 17.84 and 22.20 per cent, respectively over control. The plots with forest litter incorporated at 45 DBS had significantly higher hydraulic conductivity, per cent aggregates and mean weight diameter as compared to those incorporated at 30 DBS. However, the difference in the time of incorporation i.e., at 30 and 45 DBS had no significant effect on bulk density, particle density and water holding capacity. Incorporation of forest litter @ 3 t ha-1, 6 t ha-1 and 9 t ha-1 significantly decreased the bulk density at the rate of 3.67, 8.65 and 14.14 per cent; while particle density increased at the rate of 2.59, 3.42 and 6.61 per cent, respectively when compared to control. The addition of forest litter @ 3 t ha-1, 6 t ha-1 and 9 t ha-1 resulted in a significant increase in water holding capacity and hydraulic conductivity at a rate of 3.72, 4.65 and 6.77 per cent and 24.13, 32.30 and 41.73 per cent, respectively over control. Further, the application of forest litter @ 3t ha-1, 6 t ha-1 and 9 t ha-1 significantly increased the per cent aggregate and mean weight diameter of the soil @ 1.77, 3.49 and 6.58 per cent 17.31, 26.28 and 41.35 per cent, respectively over control. The study revealed that incorporating 9 t ha-1 of forest litter at 45 DBS had the most beneficial effect on soil physical properties.

Soil fertility evaluation of rice soils of Lumbajong block of Karbi Anglong district under hill zone of Assam through nutrient indexing

The Lumbajong block of Karbi Anglong district of Assam is characterized by undulating topography comprising of hillocks and lowland paddy fields. Cultivation of rice in traditional ways for years without adequate and balanced use of chemical fertilizers and with little or no use of organic manure have caused severe fertility deterioration resulting in stagnating or even declining productivity of the paddy field soils. Spatial distributions for organic carbon, available N, available P and available K were examined in the soil samples of selected rice fields in 102 different locations covering six villages in the block to evaluate the fertility status of the block. The study revealed that there is much variation in soil fertility status of soils developed on various land forms in the area as the soils were having low to high in organic carbon (0.42 to1.12 %), low to medium in available nitrogen (175.62 to 376 kg/ha) content; low in available P (3.86 to 28.29 kg/ha) and low to high in available K (71.68 – 439.04 kg/ha) contents. The soils of Lumbajong block were characterized as medium-medium-low-medium (MMLM) category based on the nutrient index calculated with respect to organic carbon, available N, available P and available K.

Influence of water having variable salinity and sodicity on groundnut-II : Effect on nutrient content and uptake

A pot experiment was conducted at Net House, Department of Agricultural Chemistry and Soil Science, College of Agriculture, Junagadh Agricultural University, Junagadh to assess the different levels of saline and sodic irrigation water on content and uptake of nutrient by groundnut during the Summer-2018. The treatment consists of four levels each of salinity (2, 4, 6 and 8 dS m-1) and sodicity (5.0, 10.0, 15.0 and 20.0 SAR) of irrigation water by adopting factorial CRD with three replications. The results indicated that application of different levels of saline and sodic irrigation water produced significant effect on content and uptake of N, P and K by kernel and haulm of groundnut. The highest N, P and K content (3.76 %, 0.34 % and 0.67 %) and uptake (163.6, 13.34 and 25.14 mg pot-1) by kernel and content (1.08 %, 0.15 % and 0.40 %) and uptake (177.8, 25.01 and 66.5 mg pot-1) by haulm, respectively were observed with EC-2 dS m-1 level of salinity of irrigation water, but the lowest content and uptake by kernel were observed with EC-6 dS m-1 and by haulm at EC-8 dS m-1 levels of salinity of irrigation water. There was no any pod formation were observed with EC-8 dS m-1, hence, content and uptake of nutrients by kernel considered zero. While the highest N, P and K content (2.85 %, 0.22 % and 0.42 %) and uptake (109, 5.93 and 11.45 mg pot-1) by kernel and content (1.01 %, 0.13 % and 0.37 %) and uptake (135.5, 17.80 and 48.6 mg pot-1) by haulm, respectively were observed with SAR- 5.0 level of sodicity of irrigation water. The interaction effect between salinity and sodicity levels of irrigation water on concentration and uptake of N by kernel and haulm were found significantly the highest with C1×S1 (EC- 2.0 dS m-1 × SAR- 5.0) level of salinity and sodicity of irrigation water.

Applications of synchrotron in soil science

Synchrotron radiations (SR) are emerging as a real-time probing tool for the wide range of applied sciences. Since the beginning of 1990s, synchrotron-based techniques have become increasingly employed in various fields of life science. The unique properties of Synchrotron radiations break the limits to characterize the material properties than previous laboratory based techniques. The use of SR in soil sciences also has increased dramatically in the last decade. SR techniques are used to assess soil physical, chemical and biological properties. Besides that SR techniques are also used in soil pollution studies and rhizosphere science. So this paper intends to explain about the instrument synchrotron, its techniques used in soil science and applications in soil science. Furthermore the paper tries to elucidate a few relevant researches in soil science which involves SR techniques.

Environment and plastics : A review on greener routes for plastic bottle (PET) waste management through recycling processes

Many research papers have been contributed by several authors for making polyethylene terephthalate (PET) waste recycling economically and ecologically more viable as it creates environmental hazards when disposed off after its short term use. Recycling of PET waste was started in last two decades. Most of the authors are devoting their time in getting economically viable solution for development of methods based on either mechanical or chemical recycling. Some success has been obtained in development of chemical recycling methods which provides value added products from PET waste. In this study the operating conditions and mechanism of various recycling processes available for the recycling of polyethylene terephthalate (PET) waste are reported and described.

Residual effect of different sources of nutrients on P content in maize at different growth stages in rice fallow maize cropping system

A Doctoral Research was conducted for two consecutive years (2011-2012 and 2012-2013) on fine texture soils of agricultural college farm, Bapatla to find out the residual effect of different sources of nutrients applied to preceding rice on P content in maize at different growth stages. The experiment was laidout in a Randomized Block Design in Kharif season with four treatments. The treatments consisted of M1 (RDF - Control), M2 (10t FYM ha-1 + RDF), M3 (1.5t vermicompost ha-1 + RDF), M4 (Green manuring + RDF). During the immediate Rabi, the experiment was laid out in a split-plot design without disturbing the soil for succeeding maize with the four treatments given to Kharif rice as main plot treatments and each of these divided into five sub-plots to receive five levels of fertilizer NPK application viz., N1 - 75%NPK, N2 - 100% NPK, N3 - 125% NPK, N4 - 150% NPK and N5 - 175% NPK for succeeding maize. Data collected on P content in maize at different growth stages was significantly increased with the application of 100% NPK in combination with FYM @10t ha-1 to preceding rice crop, irrespective of the NPK levels applied to succeeding maize crop. However, it was on par with that of green manuring together with 100% NPK during both the years of the study.

Soil properties as influenced by use of water having variable salinity and sodicity

A pot experiment was conducted during summer season of 2018 at Net House, Department of Agricultural Chemistry and Soil Science, College of Agriculture, Junagadh Agricultural University, Junagadh to study the influence of different levels of saline and sodic irrigation water on soil properties. The treatment consists of four levels each of salinity (2, 4, 6 and 8 dS m-1) and sodicity (5.0, 10.0, 15.0 and 20.0 SAR) of irrigation water by adopting factorial CRD with three replications. The available macronutrients (N, P2O5 and K2O) and organic carbon of soil after harvest of the crop were found maximum with EC-2 dS m-1 and SAR-5.0 level of irrigation water. The water soluble and exchangeable Ca, Mg and Na and soil properties like EC2.5, ECe, pH2.5, pHs, CEC and ESP was found maximum with EC-8 dS m-1 while water soluble and exchangeable K was found maximum with EC-2 dS m-1. The water soluble and exchangeable Na was found maximum with SAR-20.0, whereas water soluble and exchangeable Ca, Mg and K were found minimum with SAR- 20.0. The soil properties like ECe, pH2.5, pHs and ESP of the soil was found maximum with SAR- 20.0, but CEC was found maximum with SAR-5.0. The combined effect of saline and sodic irrigation water was found significant on available N and water soluble cations Ca++, Mg++, Na+, K+, exchangeable Na+, ESP, ECe and pH2.5 of soil after harvest of groundnut.

Influence of water having variable salinity and sodicity on groundnut- I : Effect on growth, yield attributes, yield and quality

A pot experiment was conducted at Net House, Department of Agricultural Chemistry and Soil Science, Junagadh Agricultural University, Junagadh to assess four levels each of salinity (2, 4, 6 and 8 dS m-1) and sodicity (5.0, 10.0, 15.0 and 20.0 SAR) of irrigation water on groundnut by adopting factorial CRD with three replications. The results indicated that application of different levels of saline and sodic irrigation water produced significant effect on growth, yield attributes, yield and quality of groundnut crop. The maximum plant height, number of mature and immature pods plant-1, weight of mature and immature pods plant-1, days to 50 % flowering, pod and haulm yield and harvest index were observed with EC 2 dS m-1 and SAR 5.0 and the lowest with EC 8 dS m-1 and SAR 20.0 of irrigation water. The quality parameters like seed index and protein content were found maximum with the saline irrigation water level of EC-2 dS m-1 and SAR-5.0, but there was no any pod formation recorded with EC-8 dS m-1. The interaction effect between salinity and sodicity levels of irrigation water on pod (8.10 g pot-1), kernel (5.36 g pot-1) and biological (26.61 g pot-1) yield were found significantly the highest with C1×S1 (EC- 2.0 dS m-1×SAR- 5.0) while no any pod formation were observed with C4×S1, C4×S2, C4×S3 and C4×S4 level of irrigation water.