Agronomic and economic study of the application of some rice cropping systems in irrigation rice land

In response to rising population growth and the increasing demand for staple foods like rice, the Indonesian government is adopting new strategies including the Jajar Legowo planting system. This research, conducted on farmland in Jebed Utara Village, focused on two factors: five rice varieties and three planting systems. The data, collected during the dry season, was assessed in a randomized block factorial experimental design. All varieties showed potential for increased productivity using the Jajar Legowo system. The 2:1 Jajar Legowo planting system yielded the highest grain output (7.99 t ha-1), marking a 15.2% increase compared to the conventional system. Additionally, it achieved the highest R/C ratio, indicating its viability as a planting system. The study suggests that adopting the Jajar Legowo planting system, particularly the 2:1 model, could significantly enhance rice production in Indonesia.


Introduction
Rice and wheat are staple foods for most of the world's population.Because of the increase in global food demand caused by population growth, every country must endeavor to augment domestic food production.As a developing country, Indonesia needs help improving its food productivity.Constraints to domestic food production include population increase, the conversion of agricultural land, and the threat posed by climate change.Indonesia is one of the Asian countries with high rice production.In 2020, Indonesia obtained around 54,649,202 tons of paddy, or 31,334,497 tons of rice [1].As one of the production centers, Central Java Province contributed 17.36% of the national rice production, which was 9,489,165 tons or 5,428,721 tons of rice equivalent [2].
According to the Minister of Agriculture, the trend of conversion of agricultural land in the 1990s reached over 30,000 hectares per year based on statistics from the National Land Agency (BPN).However, in 2011, the amount of converted land rose to about 110,000 hectares; in 2019, it reached 150,000 hectares [3].One of the issues affecting national food production is the conversion of agricultural land to other uses.The capacity of plants to adapt to climate variabilities, such as soil moisture, surface temperature, and the frequency of severe storms, is another critical limiting factor for growing food production in the face of a rise in population and dietary changes in the next century [4,5].
Climate change is an unavoidable natural phenomenon expected to greatly impact all sectors of life, including agriculture.Changes in rainfall patterns, an increase in the frequency of extreme weather events, and rising air and sea level temperatures are all serious consequences of climate change in Indonesia [6].Climate change will try to force agricultural production practices to adjust to changing environmental conditions.According to the Intergovernmental Panel on Climate Change (IPCC) fifth assessment report, Asian agriculture will continue to face temperature rises, extreme climatic events such as droughts and floods, soil degradation, and salt intrusion due to sea-level rise [7].Agriculture is  [8].Climate change impacts agricultural production in a negative way [9].Climate change endangers crop production systems, threatening the livelihoods and food security of billions of people who rely on agriculture.Prolonged droughts and floods caused by climate change and inadequate water management can drastically reduce rice production [10].Climate changes have a direct impact on planting systems and agricultural production.To create and implement strategies, it is necessary to comprehend climate variability or climate change, as well as the implications of these changes on the sensitivity of food crops and their agronomic impacts [11,12].
To maintain agricultural productivity, climate-adaptive rice cultivation technology must be developed, among them is the jajar legowo planting system [13].The Jajar Legowo planting system is one of the technological components developed to increase plant population per unit area and the border effect, both of which are expected to have an impact on rice yields [14,15], as well as the development of superior varieties with high yield potential and adaptable to climate change [6,13].
Several studies have found that the Jajar Legowo cropping system can significantly increase rice production and farmers' income.One study found that this system can increase production by 20% [15,16], while another study found that this system can increase plant population and lowland rice production by 33.07%compared to the conventional system [17,18].Meanwhile, variety-related climate change mitigation and adaptation measures include the development of early-maturing, drought-tolerant [19], submergence-resistant [20] and salinity-tolerant rice cultivars.This study summarizes research findings on the application of several rice cropping systems with climate change-adaptive improved cultivars.

Material and method
This research was conducted in Jebed utara village, Taman sub district, Pemalang district, Central Java during the Dry Season (DS II) 2018.The research used the On Farm Adaptive Research (OFAR) approach involving 15 farmers as cooperators.The study tested 5 varieties as the first factor and 3 planting systems as the second factor.Factor I (V/variety) consist of; V1: Inpari 10, V2: Inpari 19, V3: Inpari 20, V4: Situbagendit and V5: Inpago 5, while Factor II (S/planting system) consisted of S1: Conventional planting system (20 x 20 cm), S1: 2:1 jajar legowo planting system (20 x 10 x 40 cm), and S3: 4:1 jajar legowo planting system ((20 x 10) 20 x 40 cm).The experiment factorial used a randomized block design with 3 replications.The area of the experimental plot was 1000 square meters per treatment.Parameters observed included plant height at harvest, number of productive tillers, panicle length, percentage of full grains, 1000 grains weight, dry milled grain yield (t ha -1 ) and economic components.The collected data were analyzed by two-way analysis of variance (Anova) with a confidence level of 95%.Further test with Duncan Multiple Range Test (DMRT).

Sistem Tegel
Jajar legowo 2:1 Jajar Legowo 4:1 In addition to agronomic data, input, and output data of rice farming on the tegel planting system, legowo 2:1 and legowo 4:1 is also collected.Is done to determine the feasibility of rice farming in three planting systems, as an alternative for farmers to develop.The feasibility of farming was analyzed using several indictors as carried out by [21], [22] and [23] namely.

Result and discussion
Pemalang Regency is an area of 1,115.30km 2 , with paddy fields covering an area of 363.82 km 2 , of which 37.62 km 2 of rice fields are in Taman District.Taman sub-district is included in the lowlands, which have alluvial soil types.The average rainfall in this area is 256.91 mm/month [24] Most of the commodities cultivated in this area include food crops, plantations, and vegetables.The recorded paddy productivity in Taman District in 2016 was 6.12-7.19tons/ha, but in 2017, it decreased to 5.9 tons/ha.Paddy fields in this area are endemic to the main rice pests and diseases, such as Rice white stemborer, Bacterial Leaf Blight (BLB), Rats, Brown planthopper, Mealybugs, and Stink bug.

Growth component
The analysis of variance revealed that the cultivar treatment had significant variations in plant height, number of productive tillers, and panicle length.The Duncan's Multiple Range Test (DMRT), which compares treatments, was conducted after an analysis of variance.Table 1 shows that Inpago 5 produced the tallest plants, measuring 131-136.33 cm, while Inpari 20 produced the shortest plants, measuring 105-108.33 cm.Meanwhile, there were no differences in plant height between the Inpari 10, Inpari 19, and Situbagendit, all in the 108.67-116.67 cm range.The result shows that in this experiment, plant height was more influenced by genetics than environmental conditions.Furthermore, the plant height of each variety did not differ from the variety's description.The planting systems of the Tegel, Jajar Legowo 2:1, and Jajar Legowo 4:1, did not provide environmental conditions that could result in different responses to the plant height variable.However, [25] claim that there is no variation in height because rice plants are adaptable to various environments.Observations on the number of tillers indicated that each treatment produced a different plant response in terms of variety, planting system, and treatment interaction.According to Table 1, Inpari 10 developed the most tillers in the conventional planting system (Tegel), with an average of 19.07.The number of tillers employed for each variety planted with the Jajar legowo 2:1 planting system varied, with the best yield coming from Inpari 20 (18.37).Compared to all treatment combinations, the Jajar Legowo 4:1 produced the most tillers, specifically Inpari 20 (21.50), followed by Situbagendit (20.33).The variations resulting from the interaction of these treatments suggest that, in addition to variety, environmental factors influence plants' ability to produce a significant number of productive tillers.The number of tillers describes the number of new individuals that arise from a plant due to maximum nutrient intake and growth space.The findings of this study contradict previous research, which demonstrated that the number of effective tillers rose in rice with a low density over a higher density (width) [26].
However, each variety has a different response to the planting system.Based on table 1, the maximum number of tillers were produced in plants treated with the Tegel system in the Inpari 10, which was more than the Jajar Legowo 2:1.Similarly, the number of tillers with the Tegel system in the Inpari 19 was higher than Jajar Legowo 4:1.The Jajar Legowo 4:1 system produced the optimal results in terms of the number of tillers for Inpari 20 and Situbagendit.In contrast, the Jajar Legowo 2:1 produced the maximum number of tillers for Inpago 5.The difference in the number of tillers dependent on the planting system demonstrates that plant genetic potential can change in response to environmental factors, particularly the growing space.
The treatment affected the length of panicle with the treatment of varieties and planting systems, but there was no interaction effect between both.Table 1 depicts the variations in panicle length caused by the treatment of cultivars and planting systems.The Jajar Legowo system generally produced the best panicle length for all varieties compared to the Tegel system.Using the Jajar Legowo 2:1 system, plants developed the longest panicle lengths of Inpari 10, Inpari 20, and Situbagendit.While Jajar legowo 4:1 resulted in the best panicle length measurements for Inpari 19 and Inpago 5.

Yield component
The analysis results indicate that each planting system treatment responded differently to the observed yield components.The percentage component of filled grain in the Jajar Legowo 2:1 differed significantly from the Tegel and Jajar Legowo 4:1.However, the Tegel was similar to the Jarwo 4:1 system for all rice varieties.Meanwhile, the weight of 1,000 seeds was similar.The grain yield components responded significantly differently for each planting system, with the Jarwo 2:1 planting system providing the highest performance for all varieties examined.
These results demonstrate that all high-yielding varieties introduced into various planting systems continue to provide yields that are quite high (among 6.41-8.28t ha-1) above the Pemalang district average yield of 5.03 t ha-1) [24].Furthermore, it is consistent with research findings that Inpari 10, Inpari 19, Inpari 20, Situbagendit, and Inpago 5 were developed as water stress-tolerant varieties.A comparison of the yield of each variety in several cropping systems can be seen in Table 2.In general, the variety significantly impacted the percentage of filled grain, 1,000 seed weight, and dry grain.The cropping system also significantly affects the yield variables, except for the weight of 1,000 seeds.Furthermore, treatment has an interaction effect on the percentage of filled grain.Based on observations on the variable percentage of filled grain, the Jajar Legowo 2:1 gave the best effect compared to other cropping systems on all varieties tested.The percentage of filled grain produced by the interaction effect of varieties and the best planting system was sequentially created by Situbagendit x Jajar legowo 2:1 (93.17),Inpari 10 x Jajar Legowo 2:1 (91.80), and Inpari 20 x Jajar legowo 2:1 (90.57).
The interaction effect of the two treatments also appeared in the variable yield of dry grain.The combination of varieties produced the highest dry grain yields: Situbagendit x Jajar legowo 2:1 (8.26), Inpari 10 x Jajar legowo 2:1 (8.19), and Inpari 19 x Jajar legowo 2:1 (7.97).Because of interaction effects, it is unclear why each variety has a different dry grain yield in each cropping system tested.However, it can be seen in Table 2 that the jajar legowo 2:1 produces higher dry grain yields than the jajar legowo 4:1 and the Tegel cropping systems, respectively.In the other hand, the weight of 1000 grains were significantly affected only by the variety, and there was no significant effect on the three cropping systems tried.The highest average weight of 1000 grains was successively produced by Inpari 10, Inpago 5, Situbagendit, Inpari 20, and Inpari 19.

Economic analysis
The rice production analyzed is the average production of 5 varieties grown in each planting system, namely tegel, legowo 2:1 and legowo 4:1.The average production for the tegel planting system is 6,934 kg, the legowo 2:1 planting system is 7,986 kg and the legowo 4:1 planting system is 7,290 kg.The cost components are grouped by the cost of production means, labor costs and other costs (land lease and water costs) the total costs paid by farmers, 41.32% are labor costs, 41.21% rent and 17.46% are production facilities).When viewed based on the planting system, it turns out that the total cost for IOP Publishing doi:10.1088/1755-1315/1253/1/0120196 the jajar legowo 2:1 planting system is higher than that of legowo 4:1 (IDR.15,493,800,->IDR.15,135,000,-) and tegel (IDR.15,493,800,->IDR.14,878,200,-).Based on the cost component, labor wages are the highest costs in the legowo 2:1 and legowo 4:1 planting system, namely 42.57% and 41.21% of the total cost (dominated by planting costs).is in accordance with the results of [27] which states that the costs needed for the legowo planting system are higher than the tegel planting system.The results of the farm business analysis show that the income from the 3 planting systems is economically feasible.Farming jajar legowo 2:1 generates the highest income, namely IDR.20,443,200, -compared to 4:1 (IDR.17,670,000,-) and conventionals (IDR.16,324,800.-).
Other economic feasibility analyzed is BEP and R/C, the value of R/C is important to know as one of the determining factors for farmers' decisions to develop a rice farming system [28].The lowest BEP (P) value was achieved by the legowo 2:1 planting system, which is IDR 1,940/kg, this value is lower than the real price when the study was conducted, namely IDR 4,500, -thus rice farming with a legowo 2:1 planting system is faster to break even.[29] states that the sooner a manufacturer breaks even, the greater the accumulated revenue over time.
The R/C values of the rice planting system in order are legowo 2:1 (2.32), legowo 4:1 (2.17) and conventional (2.10).Economically, the three planting systems are worth working on because they are >1.Compared to the bank interest rate when conducted research, which is 6.00% / year, the choice of doing rice farming for farmers is more profitable than saving money in the bank.However, of the three rice planting systems, the Legowo 2:1 planting system is the best planting system to be used because it reaches the highest R/C value of 2.32.The research by [15] found that the Jajar Legowo planting system can increase farmers' income by up to 20% Obtaining an R/C value of 2.07 and a B/C value of 1.07.

Conclusion
The results showed that the consistent application of the jajar legowo cropping system could significantly increase rice productivity in all varieties tested.The highest grain yield was achieved for the Jajar legowo planting system 2:1 (7.99 t ha -1 ) with an increase of 15.2% from the conventional system (control).The planting system that gives a higher R/C is the application of jajar legowo 2:1, then Jajar legowo 4:1 and the lowest is the conventional cropping system, respectively 2.32 > 2.17 > 2.10.The 2:1 jajar legowo planting system provides the highest feasibility compared to other cropping systems.

Figure 1 .
Figure 1.Design rice planting system applied to research.

Table 1 .
Growth components of some variety and cropping system.

Table 2 .
Yieldd components of some variety and cropping system, in dry season 2018.
Note: Numbers followed by different letters indicate a significant difference (p<0.05).

Table 3 .
The use of production inputs of some planting system rice farming per hectare, 2018.