Development Of Upland Rice Research Articles

Participatory Plant Breeding to develop biofortified upland rice for marginal environments

Abstract In the Highlands of Madagascar, where rice is the main staple food, explosive demographic growth has driven the need for the development of upland rice. In that context, a Participatory Plant Breeding (PPB) program conducted by the FOFIFA-Cirad partnership, aims to develop upland rice varieties adapted to farmers’ needs, with superior agronomic performances, and with high grain zinc concentration. In the area, where ferralitic soils with N and P deficiencies prevail, limited fertilizer usage persists due to elevated costs, and upland rice varieties must adapt to these low fertility environments. Thus, this paper aims to identify the adequate selection conditions and methods that allow combining the above-mentioned criteria for selection. So, 56 rice breeding lines, including high-zinc genotypes, were evaluated in field trials with contrasting fertility conditions. A relative selection efficiency analysis demonstrated that selection for yield should be done in moderate fertility environments, while selection for grain zinc concentration could be done across a diverse range of conditions. Through participatory evaluations, we identified that, for this case, grain appreciation was the most important character for deciding whether to select a line, followed by productivity and earliness. We also noted that farmers were more willing to accept a variety if it had higher grain zinc concentration. Finally, we proposed a selection index that combines agronomic, farmers’ and nutritional criteria, with the purpose of selecting lines that fulfill the expectations on these areas. Overall, this paper proposes an adapted methodology for the combination of PPB and biofortification in marginal environments.

Effect of one or more microorganisms on the yield components of upland rice under greenhouse conditions

The use of beneficial microorganisms is an important strategy to improve rice production in a sustainable way. The study was carried out to determine the effect of single and combined beneficial microorganism on the development of upland rice. The experiment was performed in greenhouse and arranged in a completely randomized design with 29 treatments and 4 replications. Treatments consisted of rice seeds cultivar BRS A501 CL treated with single and combined multifunctional microorganisms (1 (Serratia marcescens), 2 (Bacillus toyonensis), 3 (Phanerochaete australis), 4 (Trichoderma koningiopsis), 5 (Azospirillum brasilense), 6 (Azospirillum sp.), 7 (Bacillus sp.), 8 to 28 (combination of all these microorganisms in pairs) and 29 (control)). Inoculation of upland rice with sole and combined microorganism on upland rice increased the roots and shoots development, yield components and grain yield of upland rice. The combinations of Bacillus sp. (BRM 63573) and A. brasilense (AbV5), Azospirillum sp. (BRM 63574) + B. toyonensis (BRM 32110) and Phanerochaete australis (BRM 62389) + Serratia marcenscens (BRM 32114) led to improved roots and shoots development; increased number of panicles and grains per pot, 1000 grains weight and grain yield of rice plants. Besides, the combinations allow helped in increased accumulation of nutrients in roots, shoots and grains of rice plants.

Land Suitability and Upland Rice Productivity with Integrated Crop Management in Sorong Regency

With Integrated Crop Management, the study is aimed at improving the production of upland rice in West Papua (ICM). On-farm research and land surveys were used to conduct this study. We looked at the following factors: 1) the suitability of the rice field in Sorong Regency, 2) the growth and production of rice plants, and 3) the social and economic factors affecting farmers. The findings indicate that upland rice development is feasible on dry land, over an area of 317,831 ha, which is made up of three types of suitable land: very suitable land (S1), which covers an area of 61,684 ha; quite a suitable land (S2), which covers an area of 59.021 ha with land constraints in the form of nutrient retention (nr); and suitable marginal land (S3), which covers an area of 197.126 ha with constraints in the form of (eh). Dry-milled grain yields in the ICM pattern with the Situ Bagendit and Batutegi varieties were 4.48 t/ha and 4.16 t/ha, respectively, greater than those in the farmer pattern. The ICM pattern has a higher profit of IDR 5,360 compared to the farmer pattern of IDR 2,400 with a B/C value of 1.6 and 1.2.

Analysis and Identification of Chemical Content of Rice of Several Strains Local Upland Rice

So far, Rice production has yet to meet domestic demand due to population growth, which continues to increase yearly. Lowland rice provides the most significant contribution to national rice production; for this reason, upland rice development is urgently needed to help increase national rice production. Central Sulawesi's upland rice germplasm is very abundant; it's just that there are still many that still need to be identified. For this reason, this study aims to identify the chemical levels of rice in several local upland rice lines. This research was conducted at the Research and Development Site of Gogo Rice, Faculty of Agriculture, Tadulako University is located at 230 meters above sea level in Kalama Hamlet III, Tamarenja Village, Sindue Tobata District, Donggala Regency, Central Sulawesi Province, with coordinates LS 00o26'51.4 BT 119o49'50,5. This research started from January to June 2023. This research was compiled using the Randomized Block Design (RAK) method with 14 local upland rice lines (Pae bohe, Menso, Maraki, Uva buya, Kalendeng, Pulau tau leru, Pulu Konta, Jahara, Buncaili, Delima, Pae dupa, Puyu tas, Tako, Dongan) and one variety of check (Situ bagendit) which was repeated three times to obtain 45 experimental units. The variables observed included moisture content, ash, protein, fat, carbohydrates, fibre and amylose. The results showed that the Pae dupa strain yielded a water content of 7.44%, protein content of 8.91%, fibre content of 3.90% and amylose content of 12.58%, while the Situ bagendit strain had a moisture content of 11.61%, ash content of 0.57%, protein content of 7.72%, fat content 0.66%.

The Diversity of Agronomic Characteristics of Several Local Aceh Rice Germplasm

To accelerate the target of national food self-sufficiency, especially rice, the development of upland rice that has high yields and is adaptive to extreme environments is needed. Fulfillment of high-yielding characteristics begins with characterization and selection to get the most adaptive varieties. This study aims to identify the morpho-physiological characteristics of Aceh rice germplasm. The study was conducted in Gampong Paloh Lada and at the Agroecotechnology Laboratory, Faculty of Agriculture, Universitas Malikussaleh, Aceh Utara Regency, and at the Biology Laboratory in Faculty of Mathematics and Natural Sciences, Universitas Sumatera Utara, from April to August 2022. This research used a Randomized Block Design non Factorial, comprising 7 local inbreds viz., Unsyiah Cakep (G1), Unsyiah Seumeulu (G2), Cot Bada (G3), Sigunca (G4), Sigupai (G5), Cot Bada (G6) and Rajasa (G7). The parameters measured were growth and yield variables consisting of plant height, number of tillers, flowering age, leaf proline content, root length, shoot-root ratio, number of grains, and weight of 1000 grains. The results indicated that the local germplasm Sigunca and Sigupai have good adaptability by adjusting plant height and forming more tillers than other germplasm. In terms of generative growth, Unsyiah Mantap and Cot Bada are entering generative growth more quickly, as marked by the appearance of flowers. The proline content as an indicator of resistance to water limitations was achieved at the highest level in Unsyiah Cakap at 5 g/mol, followed by Unsyiah Mantap at 3 g/mol.

Improving Broad Spectrum Blast Resistance by Introduction of the Pita2 Gene: Encoding the NB-ARC Domain of Blast-Resistant Proteins into Upland Rice Breeding Programs

Blast disease is generally more important in upland rather than lowland rice cultivation, representing one of the biotic obstacles in the development of upland rice. The objective of this study was to detect broad-spectrum blast resistance gene Pita2 encoding the NB-ARC (nucleotide-binding adaptor common in APAF-1, R proteins, and CED-4) domain of blast-resistant proteins in new upland rice lines from the breeding program for landrace rice varieties, with the goal of providing a novel source of blast-resistant germplasm for application in future upland rice breeding programs. In this study, we screened 19 inbred lines of landrace rice varieties challenged using local virulent isolates in greenhouse conditions and performed field evaluations to confirm blast resistance. Molecular analysis was conducted using six specific primers to detect broad-spectrum blast resistance, and sequence analysis was performed to detect the NB-ARC domain of blast-resistant proteins in the lines. Consistent results were observed between greenhouse screening and field evaluations, although there was variance in the level of resistance. The PCR assay showed that there were eight positive lines (G7, G8, G9, G11, G13, G14, G15, and G18) containing the Pita2 gene. Conserved domain analysis revealed that eight blast-resistant rice lines encode NB-ARC at sequence lengths ranging between 300 and 870 (450 bp). Using these sequences in BLASTX searching revealed 15 gene homologs of the eight rice lines, which were detected as Pita2 genes, with a similarity level of 81–99%. Further comprehensive studies should be performed to confirm the performance and resistance of candidate lines in field trials in various blast-endemic areas before being released as new upland rice varieties able to overcome the problem of blast disease in the field. In addition, the lines can also be used as a novel genetic resource in the blast-resistant upland rice breeding program on various rice cultivars.

Morphological Structure of Upland Rice Varieties at Different Light Intensities

Increasing food self-sufficiency, especially rice grown as intercrops, requires attention to the development ofupland rice varieties that are shade-tolerant and capable of high production. The objective of this research tostudy about the mechanism of tolerance, morphological characters as characterizing tolerance to shade. Theresearch was carried out in Cengkeh Turi Binjai with an altitude of ± 32 meters above sea level, with soil pH;4.5, started from May to August 2018. The study used a split plot design with two factors. The first factorwas the light intensity, consist of: 100%, 75%, 50%, and 25%. The second factor consisted of 5 rice varieties,namely: Inpago 5, Lipigo 4, Inpago 8, Inpago 10, and Lipigo 2. The result of this study was an increase in thearea of the flag leaf with a decrease in sunlight intensity by 75%. The conclusion of this study is that thelower the intensity of sunlight, the lower the angle of the flag leaf and the thickness of the upland rice leaf.Keywords: light; upland rice; varieties

The Effect of The Application of Soil Biostructures Created Using Biochar and Seaweed Extract on Upland Rice Growth

Earthworms play an important role in mixing soil particles with biochar grains, as well as creating biostructures, and the application of seaweed extract to soil affects the microbes within, as well as plant growth. This study, therefore, aims to investigate the effect of mixing soil, teak leaf biochar, as well as seaweed extract on the arbuscularmycorrhizal fungal (AMF) spores within the biostructures formed, and analyze the effect of applying these biostructures to planting media soil on the growth and yield of local upland rice. Before the experiment, extract stock from Sargassum sp. was diluted with water into five separate concentration levels, 0%, 20%, 40%, 60%, and 80%. Subsequently, 20 individual earthworms were released on the soil surface previously mixed with biochar and seaweed extract in a reactor. The planting media used in this study was soil from the cogongrass area with grain sizes below 4 mm, and about 10% (w/w) of the biostructures formed were added to the media in a polybag, then the mixture was transplanted with upland rice seedlings of local variety Sorawolia.According to the results, the treatment containing had the highest total AMF spores. Furthermore, the addition of biostructures significantly affected plant height, leaf number as well as area, and the number of tillers at 42, 42 to 70, and 70 days after application, respectively. Meanwhile, the highest plant dry weight and panicle length were obtained from the treatments containing 80% and 60% extract stock, respectively. However, there was no significant difference in the spikelet number and percentage of filled spikelets between the biostructures. Therefore, the application of both teak leaf biochar and extract of Sargassum sp. was concluded to be able to improve the performance of earthworms (Pheretima sp.) in creating soil biostructures containing AMF spores, for local upland rice development in conditions of poor soil fertility. However, future studies are required to investigate this application’s potential as a source of inoculum for AMF spores or other beneficial microbes, for application at the smallholder farm level.

PROSPEK PENGEMBANGAN PADI GOGO MENDUKUNG LUMBUNG PANGAN DI WILAYAH PERBATASAN PULAU MOROTAI

Upland rice commodity is generally the second choice after paddy in fulfilling community rice needs. Morotai Island is one of the government's target locations in initiating the Export-Oriented Food Storage program in the Border Region. This study aimed to determined the prospects for the development of upland rice to support food barns in the border region of Morotai Island. The method used is descriptive analysis, measuring the growth rate of rice based on the Compound Annual Growth Rate (CAGR), and measuring the feasibility of farming using income analysis, R/C ratio, and break-even point analysis. The results showed that the increase in the growth rate of harvested area and upland rice production was 25,75 percent with a contribution of 42,81 percent and 31,65 percent, recpectively, of the harvested area and rice production on Morotai Island in the 2011 to 2017 period. Upland rice farming has an R/C ratio of 1.72 which indicated that this farming is feasible. The potential and opportunities for upland rice development to support food barns on Morotai Island are still very prospective. The development of upland rice can be pursued through intensification and extensification of agriculture with the application of cultivation technology, the use of new high yield varieties, increasing the cropping index, and sustainable soil and water conservation efforts. This needs to be supported by strong farmer and extention institutions and easy access for farmers to finance agriculture.

Prospek Pengembangan Padi Gogo Mendukung Lumbung Pangan di Wilayah Perbatasan Pulau Morotai

Upland rice commodity is generally the second choice after paddy in fulfilling community rice needs. Morotai Island is one of the government's target locations in initiating the Export-Oriented Food Storage program in the Border Region. This study aimed to determined the prospects for the development of upland rice to support food barns in the border region of Morotai Island. The method used is descriptive analysis, measuring the growth rate of rice based on the Compound Annual Growth Rate (CAGR), and measuring the feasibility of farming using income analysis, R/C ratio, and break-even point analysis. The results showed that the increase in the growth rate of harvested area and upland rice production was 25,75 percent with a contribution of 42,81 percent and 31,65 percent, recpectively, of the harvested area and rice production on Morotai Island in the 2011 to 2017 period. Upland rice farming has an R/C ratio of 1.72 which indicated that this farming is feasible. The potential and opportunities for upland rice development to support food barns on Morotai Island are still very prospective. The development of upland rice can be pursued through intensification and extensification of agriculture with the application of cultivation technology, the use of new high yield varieties, increasing the cropping index, and sustainable soil and water conservation efforts. This needs to be supported by strong farmer and extention institutions and easy access for farmers to finance agriculture.

Utilization of suboptimal land for the sustainability of upland rice farming in Minahasa District

Increasing rice production is not only relied on from irrigated and rainfed rice fields, but also on dry land (upland rice). Development of upland rice on sub-optimal lands is one of the efforts to overcome the problem of vulnerability to rice availability, but until now its management is still not optimal. Minahasa District is one of the upland rice producing districts in North Sulawesi. This paper aims to identify matters related to sub-optimal land use for the sustainability of upland rice farming by farmers that can be developed in support of efforts to increase upland rice production in North Sulawesi, in addition to improving the existing technology used by farmers. This study was conducted in the Tombariri Subdistrict, Minahasa District, using a survey method. Data collection was carried out through field observations, surveys, documentation, in-depth interviews with key informants, and literature studies. The data obtained were then analyzed descriptively. Based on field identification and the results of the study, it was found that the existing local farmers’ technology was still very simple, especially in the aspects of seed supply, planting and maintenance. Farmers are increasingly pursuing development towards organic farming. There are still many sub-optimal land uses that can be optimized for upland rice cultivation accompanied by improvements to the existing limiting factors on each land.

Does the glufosinate-ammonium herbicide have the potential to induce the hormesis effect in upland rice?

This study aimed to evaluate the effects of low doses of the herbicide glufosinate-ammonium in different application modes in the vegetative development of upland rice. The treatment consisted of a combination of five low doses (0; 15; 30; 60; and 100 g a.i. ha−1) of the herbicide glufosinate-ammonium and four application modes of the low doses: single between active tillering (AT) and floral differentiation (FD); single after FD; split in two (the first at the beginning of the AT and the second between AT and FD; split in three (the first at the beginning of the AT, the second between the AT and the FD and the third after the FD, with. There was no hormesis effect on rice crop due to low doses of glufosinate-ammonium. The vegetative development of rice plants was reduced by the application of low doses in all application modes with lower plant height, dry weight, number of panicles, and effective tiller.

Hydro- and Osmo-priming Effects on Upland Rice Exposed to Drought Conditions at Vegetative and Reproductive Stages

Drought stress during vegetative and/or generative stages could cause massive reduction in rice yield. This study evaluated effectiveness of hydro- and osmo-priming on improving seed germination, growth and development of upland rice under drought stress during late vegetative, booting, or heading stage. Treatments consisted of hydro-priming and osmo-priming consisted of three polyethylene glycol (PEG) concentrations i.e. 10%, 15%, and 20%. Results showed that application of osmo-priming at 10% PEG required longer time (21.93 hours) to reach 50% germination, lower germination and lower vigor index. However, after germination, seeds primed with 10% PEG exhibited better seedling growth than other seed priming treatments. Effects of seed priming on yield components were overshadowed by drought exposures. Drought imposed during vegetative stage did not significantly affect yield; however, regardless of seed priming treatments, yield reduction was inevitable in rice plants exposed to drought during booting or heading stages. Rice plant shortened time to reached physiological maturity as an adaptive mechanism if drought treatment was applied during heading stage. Keywords: Germination, Polyethylene glycol, Seedling growth, Seed priming, Yield component

Cover crops and multifunctional microorganisms can affect development of upland rice

Cultivation of cover crops in the off-season and the use of multifunctional microorganisms are strategic technologies to ensure sustainability in upland rice production. The objective of this work was to determine the effect of mix of cover crops cultivated in the off-season and multifunctional microorganisms on the growth promotion of upland rice plants, under no-tillage systems conducted in the Brazilian Cerrado. The experimental design was a complete randomized blocks in a 6x2 factorial scheme with four replications. The treatments consisted of a combination of six soil covering plants 1. Fallow (control); 2. millet (Pennisetum glaucum) and crotalaria (Crotalaria juncea, C. spectabilis and C. ochroleuca); 3. millet and pigeon pea (Cajanus cajanus); 4. millet and Urochoa ruziziensis; 5. millet, U. ruziziensis and pigeon pea; and 6. millet and buckwheat (Fagopyrum esculentum)), with or without the application of coinoculants 1301 (Bacillus sp.) + Azospirillum sp. The mix of cover crops millet + U. ruziziensis and millet + U. ruziziensis + pigeon pea recorded the largest biomass production and the highest nutrient content in the straw. Rice plants cultivated after millet + pigeon pea showed largest transpiration and stomata conductance. The application of multifunctional microorganisms contributed to an increase of 29% in the photosynthetic rates of rice plants. The highest upland rice grain yield was achieved after mix of millet + crotalaria (Crotalaria juncea, C. spectabilis and C. ochroleuca). The application of multifunctional microorganisms increased the mass of 1000 grains, but does not affect rice grain yield. Our results showed that cover crops significantly affected rice grain yield and the multifunctional microorganisms affected grain quality

Farmers’ Adoption of Upland PalayCheck System under Upland Rice Development Program (URDP) Implementation In Northern Philippines

The Community-based Upland PalayCheck System under the Upland Rice Development Program was used as a platform of implementation. It has eight (8) KeyChecks as farmers’ best practices and technologies in upland rice production. The study described the socio-demographic profile, institutional factors, biophysical factors, and economic factors of the farmer respondents. Moreover, it described the perceived effectiveness of Farmers’ Field School (FFS) on Upland PalayCheck System, upland community seed banking, and community-based upland palayamanan. Also, the relevance, comparability, traceability, and ease of the practice of the technologies and practices under the Upland PalayCheck System were determined. Also, respondents’ rice production practices and the percentage of adoption under the Upland PalayCheck System were assessed. Furthermore, factors that influence the level of adoption of the Upland PalayChck System were determined. Barangay Kilig and Caragasan were selected as the locale of the study because these were the pilot site of the project in the municipality. The study was conducted through a survey questionnaire and focus group discussions. Respondents were active participants of FFS on the Upland PalayCheck System. Qualitative data were analyzed through SPSS, however, thematic analysis was done to analyzed the reasons of respondents. The result shows that there were more female farmers in the area. Thus, the introduction of technologies should be more gender sensitive. Moreover, the majority of them were elementary level and have limited access to training except for the said FFS. These farmers were mostly owners of their land and the majority manage more than 2 ha. Thus, they need more capital in their farm operation. Also, they get their capital from cooperatives and microfinance which may bring them deep indebtedness if they do not get a good yield. Also, farming was their major source of income in the area. Therefore, they should have given other ventures in agriculture for a living. Furthermore, they get technical advice mostly from technical experts radio and leaflets. However, extension contact was only at least once a month due to the large proportion of extension workers over a number of farmers. Furthermore, the majority of the upland areas of the farmers were low soil fertility. Also, the majority of their field received low precipitation resulting in drought. Nevertheless, upland rice farming can be considered as a good alternative crop in the uplands because of its promising higher average selling price at 25.48% of premium varieties. However, seldom of them were selling their products because it is more for their food consumption. The latest average yield (2.40 t/ha) of farmer respondents was greater than the previous average yield in the municipality (>1.0/ha). Farmers Field School (FFS) on the Upland Community-based Palayaman System was used as a platform to disseminate the objectives of the URDP. The level of effectiveness of farmers on Upland FFS, CSB, and Upland Palayamanan was also assessed. The result shows that the conduct of Upland FFS and overall impressions to URDP were agreed to be very effective. Respondents stated that they gained more knowledge of upland rice farming and increase their yield. Moreover, they have learned to address their problems in upland rice production.

Effects of contrasted cropping systems on yield and N balance of upland rainfed rice in Madagascar: Inputs from the DSSAT model

AbstractIn response to the extensive development of upland rice on the hillsides of the Malagasy highlands, alternative cropping systems have been designed based on conservation agriculture (CA). As the promotion of CA in smallholder farming systems is still the subject of debate, its potential benefits for smallholder farmers require further assessment. In the context of resource-poor farmers and low-input production systems, nitrogen (N) is a major limiting nutrient. The effects of contrasted cropping systems have been studied on upland rice yield and N uptake in rainfed conditions: conventional tillage (CT) and CA with a mulch of maize or a legume (Stylosanthes or velvet bean). Decision Support Systems for Agrotechnology Transfer (DSSAT) crop growth model was used to quantify the soil N balance according to the season and the cropping system. The lowest yields were obtained in CA with a mulch of maize and were also associated with the lowest crop N uptake. Upland rice yields were higher or equivalent under CA with a legume mulch than under CT cropping systems. The supply of N was considerably higher in CA with a legume mulch than in CT, but due to higher leaching and immobilization in CA, the final contribution of N from the mulch to the crop was reduced although not negligible. DSSAT has been shown to be sufficiently robust and flexible to simulate the soil N balance in contrasting cropping systems. The challenge is now to evaluate the model in less contrasted experimental conditions in order to validate its use for N uptake and yield prediction in support to the optimization and design of new cropping systems.

The analysis of selection of upland rice variety in East Aceh District

The aim of this research was to determine important parameters based on farmers’ perceptions and the selection of the best alternative varieties for the development of upland rice in East Aceh. Data collected includes secondary data and primary data. Primary data collection is done by using questionnaire data in gathering information on farmers’ perceptions. Whereas the alternative selection combines elements of farmers’ perceptions and field observations of several varieties. The analytical method was carried out using observations in the field and processing data descriptively. The varieties used in the field study were Inpago 8, Inpago 9, Inpago 10, Inpago 11 and Situ Patenggang. The results of the study address important parameters in the cultivation of upland rice based on the results of the questionnaire with farmers are the age of fast harvesting plants and the average production with a very important category, then the weight of 1000 seeds in grams and the potential yield with important categories, then the productive tillers of each stem, the amount grain of each panicle (seeds) and tall plants in the Medium category. The choice of the best alternative varieties in East Aceh Regency based on the results of farmers’ perceptions and field studies were found in Inpago 9 varieties.

Upland rice gas exchange, nutrient uptake and grain yield as affected by potassium fertilization and inoculation of the diazotrophic bacteria Serratia spp.

Potassium (K) is the second most uptaken nutrient by upland rice crops. Beneficial microorganisms, such as Rhizobacteria participate in different processes that affect transformation of soil nutrients, making them available to plants. However, there are no information about the use of Rhizobacteria and different rates of K fertilization in this crop. To elucidate this interaction, the objective of this study was to determine the effect of the rhizobacteria Serratia spp. strain BRM 32114 and doses of K at sowing fertilization on upland rice development. The experimental design was a complete randomized block in a factorial 4 × 2 scheme with four replications, under no-tillage systems conducted in the Brazilian Cerrado during 2015/16 and 2016/17 growing seasons. The treatments consisted of four K2O doses (0, 20, 40 and 60 kg ha-1) without or with rhizobacteria applied three times in the field (on the seeds, sprayed over the soil, seven days after sowing and sprayed on the plants, 14 days after sowing). Biomass production, gas exchange, nutrient content in leaves and grain, yield components and grain yield were evaluated. The use of BRM 32114 applied in soil with high levels of K provided increase in the contents of P, Ca, Mg, Fe and Zn in rice leaves. The results showed enhances in plant biomass (7.2%), the number of panicles per plant (10%), and the grain yield of upland rice (16.3%). Therefore, our results allow inferring that the use of microorganism BRM 32114 provided significant improvements in rice growth/development, which resulted in higher grain yield over two consecutive growing seasons under field conditions. It showed that the bioagent Serratia spp. is promising to be incorporated into crop systems.

The Potential Areas for Crop Development in Morotai Island Regency, Indonesia

The needs of food in Morotai Island Regency always increase over time, along with the increase in population. On the other hand, the available food potential is still low in productivity to meet the needs. Crop development in Morotai Island Regency, as an effort to fulfill local food needs, can still be done because the land resources potential is available and not optimally utilized. Agricultural land is the main resource for rural community development and food supply. The objectives of this research are: (1) To find out the potential of land resources and availability for crop development in Morotai Island Regency; (2) Identifying the advantages and prospects of crop development in Morotai Island Regency and (3) Preparing the recommendations for the development and management of land for crops in Morotai Island Regency. Data analysis consists of the needs and advantages of crops, farming feasibility, income, revenue, and land suitability. The results show that the suitable (S) land potential for the development of crops reaches 55,624.7 ha. Potentially suitable land for lowland rice, which classified as sufficiently suitable (S2), reaches 34,290.5 ha and marginally suitable (S3) land reaches 7,282.5 ha. Sufficiently suitable (S2) and marginally suitable (S3) lands for upland rice reach 25,040.3 ha and 28,932.8 ha respectively. As for corn cultivation, sufficiently suitable (S2) land reaches 25,040.3 ha and marginally suitable (S3) lands reaches 28,932.8 ha. Development of food crops as a result of analysis of harvested LQ shows that base food crops in South Morotai District are wetland rice (1.06), corn (1.02). East Morotai sub-district is based on the development of wetland rice (1.14) and upland rice (1.02). Morotai Selatan Barat Subdistrict is the base for the development of lowland rice (1.42). North Morotai District is the base for the development of upland rice (1,15). While Morotai Jaya is the base for developing upland rice (1.49), corn (1.53). Leading crop/s in South Morotai District are lowland rice and corn; Southwest Morotai is lowland rice; East Morotai are lowland rice and upland rice; North Morotai is upland rice; and Morotai Jaya are upland rice and corn.

Cover Crops as Affecting Soil Chemical and Physical Properties and Development of Upland Rice and Soybean Cultivated in Rotation

Cover crops can provide changes in soil chemical and physical properties, which could allow a sustainable development of soybean and upland rice rotation in Brazilian Cerrado. The objective of this study was to determine the effects of cover crops (cultivated in the offseason) in the soybean-upland rice rotation (cultivated in the summer season) on the soil chemical and physical properties, yield components and grain yield of the cash crops. The experimental design was a randomized block design in factorial scheme 4×2 with six replications. Treatments were composed by four cover crops: fallow, millet (Pennisetum glaucum)+Crotalaria ochroleuca, millet+pigeon pea (Cajanus cajans), and millet+pigeon pea+Urochola ruziziensis in the offseason with one or two cycles of cover crops, with rice (Oryza sativa) or soybean (Glycine max) in the summer season. Cover crops alone provided no changes in soil chemical properties. However, the rotation cover crops/cash crops/cover crops/cash crops reduced pH, Al and H+Al and increased Ca, Mg, K and Fe contents in the soil. The cover crops millet+pigeon pea and millet+pigeon pea+U. ruziziensis improved soil physical properties in relation to fallow, especially in the 0–0.10m soil layer. In spite of the improvement of the soil physical properties after two years of rotation with cover crops and cash crops, the soil physical quality was still below the recommended level, showing values of macroporosity, S index and soil aeration capacity lower than 0.10 m3/m3, 0.035 and 0.34, respectively. Upland rice production was higher under mixtures of cover crops than under fallow, mainly because of soil physical changes done by these mixtures of cover crops. Soybean grain yield was similar under all cover crops tested, but was higher after the rotation cover crops/upland rice/cover crops than after only one cycle of cover crops.