Effects of cropping system and varieties on the rice growth and yield in acid sulphate soils of tidal swampland

Swampland plays a critical function in agriculture, specifically in growing rice production. The study aimed to determine the effects of cropping systems and varieties on the rice growth and yield in acid sulfate soil of tidal swampland. The experiment was conducted in a potential acid sulphate soils in Kapuas Regency, Central Kalimantan Province. The experiment was arranged in a split plot design with three replications. The main plot consisted of three HYV’s of rice, namely Inpara 8, Inpari 32, and Margasari. The subplot consisted of five cropping systems, namely, Jarwo 2:1A, Jarwo 2:1B, Jarwo 2:1C, Hazton, and Tegel. The plot size was 4 m x 5 m. The variables observed included initial soil properties, plant growth, and yield components. The jajar legowo cropping system in this study was not able to increase rice yields in acid sulphate soil. There was an interaction effect of cropping systems and varieties on the plant height and number of tillers at vegetative phase. At generative and pre-harvest phases, there was significant single effect of variety and cropping system in the planting height and number of tillers, respectively. Both cropping system and variety significantly affected the number of panicles per hill, while panicle length, grain per panicle and grain yield were only affected by variety. There was no significant effect of both factors on the number of filled grains per panicle. Inpara 8 variety achieved the highest grain yield, which was 6.78 ton.ha-1 or equivalent to 4.34 ton.ha-1 of 14 % water content.

Combining ability and heterotic value of ten lines maize genotypes tolerant to tidal-swamp soil stress

Development of maize hybrid for tidal swampland was initiated by selecting and combinate some superior line genotypes that tolerate to the restrictions in target environment. This study aimed was to evaluate the capability of ten maize lines result of selection on tidal swamp acid sulphate soils to obtain GCU, GCA, and heterosis values based on parental yield averages. The experiment has consisted of ten fine line genotypes which have selected in 2019 at the tidal swamp. Each parent was crossed in half-diallel combination, resulting in 46 entries, including the inbred parents. The entries were planted in a randomized complete block design with three replications. The research was conducted on Bajeng Research Station Experiment 5°18’S and 119°30’E from September 2020 to January 2021. The result shows that GCA ability and SCA ability was significant to yield in the form of grain (15% moisture content), the number of ear per plot, ten ear weight, ten corncob weight, ear harvested weight, 1000 seeds weight, plant height, ear length and the number of seed per ear. Grain yield of W6xW9 crosses obtains the highest value of 9.36 tha−1, non-significantly different to hybrid check P35 (9.35 tha-1). The highest GCA value in the grain yield character was obtained on W9 parental line (0.64**). The highest SCA was obtained on the crossing of W7 x W8 (2.61). The highest heterosis value was revealed in W5 x W10 hybrid (4.80). However, W7 x W8 crossing heterosis value was 2.34, indicate that a high SCA effect did not usually generate high heterosis. To perform high heterosis value, W10 was good as female parental.

The Potential of Central Kalimantan’s Local Orchid as Material Source for Genetic Improvement

Central Kalimantan Province with total area of 15.380.000 ha or about 7.93 % of Indonesian areas consists of coastal regions and forest areas has potential biodiversity such as Orchidaceae. This region has various type of lands involving peat lands, swamplands with acid sulphate soils and up lands. The existence of orchid in Central Kalimantan’s forest can be found scattered in forest areas with high diversity life, form and uses. The methodology used include exploration and collection and they were conducted at six districts, i.e. East Barito, South Barito, North Barito, East Kotawaringin and Murung Raya, starting from March 2016 until December 2018. The objective of this study was as follows: (1). The exploration process, (2). The ex-situ and in-situ conservation, (3). The characterization process, (4). The documentation process. The results of these activities shown that there are several ex situ collection of 8 accessions of medicinal plants that can be used as a source of material for genetic improvement. The orchid plant’s conservation can be conducted through in-situ and or ex-situ. In-situ conservation can be conducted through managing forest areas as the natural habitat of the material for genetic improvement, while for ex-situ conservation, it can be managed outside of the native habitats. Appropriate utilization and research activities are important in conservation of the material for genetic improvement in Central Kalimantan

Acid Mine Drainage (AMD) and Acid Sulphate Soil monitoring using mineral and image spectroscopy: hyperspectral and multispectral approaches

<p>Mining generates a number of significant environmental impacts, such as increased acidity of the soil/water environment, called mineral Acid Mine Drainage (AMD) being produced when sulphide-bearing material is exposed to oxygen and water.  Similar problem represent acid sulphate soils which are naturally occurring soils containing iron sulphide minerals (predominantly pyrite) or their oxidation products. Once these soils are drained, excavated or exposed to air by a lowering of the water table, the sulphides react with oxygen to form sulfuric acid. For both AMD and acid sulphate soils, there is a lack of historical and update records and, consequently, there is a need for new monitoring techniques allowing systematic analysis. A systematic study on how to map mineral patterns that characterize these acid environments using proximal remote sensing and imaging spectroscopy is presented. Furthermore, the upscaling to the spectral and spatial resolution of the satellite data such as WorldView2/3 and Sentinel-2 is discussed as well as an issue of transferability of the developed methods between the test sites which are characterized by different geographical conditions and environments.</p>

Limitation and Recommendation for Rice Cultivation on the Problem Soils in the Southern Region of Vietnam

Background: Soil degradation is the factor causing crops yield decline in the Southern region of Vietnam. Since the recommendations for limitation of soil constraints will consult the proper problem soil management. Methods: The soil limitation identified based on soil chemistry, physics and morphology properties, suggested by Sanchez et al (1998 and 2003). Soil data of 28 field experiments were analysed. Result: There were 25 rice soil fertility classes, among those, CC (clay in top and subsoil) and CCs (clay in top and subsoil, saline affected) types occupied in large areas. The major soil limitation for rice cultivation including soils low in % organic carbon (o); high in P fixation and high Fe toxicity potential (i); potential salinity (s-); low available P (p); low pH and high Al (a); actual acid sulphate soils (c, c-) potential acid sulphate soils (f, f-). The leaching soil toxicity, application of N, P, K fertilizers and organic matter were recommended.

Soil Carbon Stock and Pools in Acid Sulphate Soils of Kerala

A study was conducted to assess the soil carbon storage as different soil carbon pools in acid sulphate soils of Kuttanad, Kerala under different land uses and mapping of carbon stock using GIS. Surface soil samples (0-15 cm) were collected from three agricultural land use systems namely rice, coconut and rice-fish from six acid sulphate soil series viz. Ambalapuzha, Purakkad, Thakazhi, Thuravur, Thottapalli and Kallara and were analysed for soil carbon pools like organic carbon, labile carbon, water soluble carbon, particulate organic carbon, microbial biomass carbon and mineralizable carbon using standard procedures .The carbon stock in soil was also computed and mapped using Arc GIS software. The highest organic carbon content of 9.38% was recorded in Kallara series under rice land use. The water soluble carbon ranged from 44.38 to 208.68 mg kg-1. Labile carbon in soil varied form 4.36 mg g-1 to 13.06 mg g-1. Particulate organic carbon was the highest in rice land use in Kallara series (7.23%). The mineralizable carbon ranged from 2.17 mg kg-1 to 2.91 mg g-1. The microbial biomass carbon varied between 71 mg kg-1 and 488 mg kg-1. The humic acid content varied from 0.20% to 6.09% and the fulvic acid content ranged from 0.09% to 20.10%. The active and passive carbon pools and their contribution to total soil carbon pool was the highest in Kallara series. Among the different land uses, coconut had the highest active pool, while rice land use recorded the highest passive pool of carbon. The soil organic carbon stock (115.96 Mg ha-1) and carbon pool index (2.10) were the highest in Kallara series. The proportion of POC to SOC was the highest in Kallara series (0.62) under rice land use indicating it as a potential carbon sink. The carbon turnover rate was found to be the highest in Thottapalli series (1.15) under coconut land use indicating it as a potential carbon source.