Rice (Oryza sativa L.) is the most widely produced and consumed food for a large part of the world's human population, most importantly in developing countries (Seck et al., 2012). It has also become a priority commodity for food security in Africa and has grown over 75% of the African countries with a total production of 14 million tons and 16 million metric tons of consumption annually (MoARD, 2010). At present rice is gaining the same importance as some of the most common cereal crops for both domestic consumption as well as market use in Ethiopia. Currently, it is the most crucial blending crop for enjera preparation in different parts of Ethiopia. The national production area in 2019 was approximately 57 thousand hectares with 170 thousand tonnes of paddy rice with an average yield of 2.96 tonnes per hectare. The production area of rice in Ethiopia increases from 29 to 90 thousand hectares from 2010 to 2019 (FAOSTAT, 2019). It indicates the rapid distribution of rice production to different parts of Ethiopia as a staple food crop. The highest grain yield recorded in research plots was 5.4 t ha^-1 in Ethiopia (Tadesse, 2015). However, the national productivity of the crop is still far below the potential of the crop in major rice-producing countries; 4.0 t ha^-1 in India, 5.1 t ha^-1 in Indonesia, 5.9 t ha^-1 in Vietnam, and 7.0 t ha^-1 in China, and 8.8 t ha^-1 in Egypt.

The lowlands of Gimbo in the Kaffa zone are one of the potential areas for rice production, mainly in rain-fed upland ecology. The crop plays an important role for farmers in the area, used as food for home consumption and income source. Bonga Agricultural Research Center has been conducting several variety improvement trials on rice so far. Consequently, several released varieties were evaluated and the best varieties were identified and recommended for production. However, the productivity of these varieties have been declining gradually due to the use of poor management practices. Therefore, it is necessary to study the effect of agronomic management practices on the yield performance of local and improved upland rice varieties to determine and promote the best practices in the area.

Description of the experimental site
The field experiment was conducted at Choba kebele in the Kaffa zone. Choba is located about 53 kilometers far away from the town of the district, Gimbo. The study area represents the lowland agroecology of the district. It is situated at 07° 24’ N latitude and 36o 26’ E longitude at an elevation of 1430 meters above sea level. Mean monthly values are in the range of 125-250 mm. The mean temperature ranges from 18.1 to 21.4°C. The soil type is characterized by Vertisols (BoNRD, 2018).

Materials Used for the Experiment
NPS (48% P2O5, 19% N, and, 5% S), and Urea (46% N) were used as inorganic P2O5 and N sources.

Planting Material
The improved rice variety Suparica-1 and local cultivar were used as a test crop.

Treatments and Experimental Design
The experiment was conducted during the main cropping seasons of 2019 and 2020. Treatments consisted of improved management practices with Suparica-1, improved management practice with local cultivar, Farmers practice with Suparica-1 and farmer’s practices with local cultivar.Improved management practices used were growing of suparica-1 with row spacing of 2.5cm, seed rate of 80 kg ha^-1, three times tillage, three times weeding, application of fertilizers at the rate of 100 kg NPS and 100 UREA per hectare and farmer's practices were growing local cultivar sowing with broadcasting, using unfixed seed rate, till twice, weed once with herbicide application and without fertilizer application. The rate and time fertilizer application for improved management practices were done as per the recommendations. The experiment was laid out in a randomized complete block design replicated three times considering farmers as replication. A large plot size of 5 m x 10 m area was used.

Data Collection and Measurements
Growth parameters
Plant height: was determined by measuring the length of ten randomly selected sample plants from the ground level to the tip of the panicle in each plot at physiological maturity.

Panicle length: done by measuring the length of the panicle from the node where the first panicle branch emerges to the tip of the panicle and determined from an average of ten randomly selected plants per plot.

Yield and yield components
The number of tillers (both productive and unproductive) per m²: The numbers of tillers were determined by counting the tillers from an area of 0.5 m x 0.5 m row plants by using a quadrant in each plot and then converting to a square meter area.

The number of panicles per m2: The number of panicles was determined by counting the panicles from an area of 0.5 m x 0.5 m row plants of each plot and then converted to a square meter area.

The number of total spikelets per panicle: The number of spikelets was determined by counting all spikelets (filled and unfilled) from ten randomly selected panicles of ten sample plants in each plot and averaged.

The number of filled spikelets per panicle: The number of spikelets was determined by counting only filled spikelets from ten randomly selected panicles of ten sample plants in each plot and averaged.

Thousand-grain weight: was determined by weighing randomly drowned 1000 grains of the well-developed, whole, or undamaged grains and then adjusted to 14% MC.

Grain yield: grain yield was determined by harvesting the rice crop from the plot area, threshed, cleaning, and weighing using an electronic balance, and then adjusted to 14% moisture content.

Statistical Analysis
The collected data were subjected to analysis of variance (ANOVA) using proc Anova procedures of SAS version 9.3 (SAS Institute, 2002-2010). The treatment means of significant treatment effects were compared using the Least Significant Difference (LSD) test at a 5% probability level (p<0.05).

Partial Budget Analysis
It was performed using the average grain yield to detect economically gainful management practices. The yields of all treatments were adjusted downward by 10% to reflect possible lower yields expected by the farmers due to differences in management factors. The price of seed was ETB 12 and 15 per kg for local and improved variety, respectively. The local wage rate was ETB 70 per person per day was considered under variable costs. The farm gate price of grain was ETB 10 and 12 per kg for local and improved variety, respectively. A gross farm gate benefit was obtained by multiplying adjusted yield (kg ha^-1) with farm gate price (ETB kg-1); while the marginal rate of return for each treatment was calculated as change of benefit divided by change of cost and multiplied by 100 CIMMYT. 1988. However, economic advantages were determined by arranging treatments in order of increasing costs and then considering MRR between each treatment. Finally, the treatment with the highest MRR was recommended for production.

A combined analysis of variance showed a significant (p < 0.05) difference among treatments for grain yield and other parameters studied (Table 3). The highest grain yield (4516.0 kg ha^-1) was recorded for improved variety under improved agronomic management practices. However, the lowest grain yield was recorded both for improved variety (2534.8 kg ha^-1) and local cultivar (2954.0 kg ha^-1) when grown under farmers’ management practices. On the other hand, both the local cultivar and improved variety performed well under improved agronomic management practices. The local cultivar grown under improved management practices gave a 24.5% yield advantage over farmer’s practices. However, improved variety showed poor performance under farmer’s practices, which had a 14.2% of yield reduction as compared to the local cultivar under the same management practice. Improved varieties have a high response to improved management practices, particularly for fertilizer application. In addition, rice is sensitive to weed competition, especially at early growth stages. Weed can cause yield reduction in rice up to 30-35%. The yield advantage of 43.9% and 24.5% was recorded with improved variety and local cultivar, respectively when grown under improved agronomic management practices over farmer's practice. This indicates the possibility to increase the productivity of upland rice sustainably using improved agronomic management practices recommended for a specific crop variety and location. Therefore, it is difficult to promote the yield response of a given improved variety without fulfilling its requirements which were suggested by experts during variety development. Adopting a consistent crop variety and agronomic management system on a farm will develop a more resilient crop production system and provide more sustainable crop yields (Walia, 2021).

A partial budget analysis was also carried out to check the profitability of management practices to compare treatments because of economic profitability rather than only looking at the maximum biological yield (CIMMYT, 1998). Based on this, the highest net benefit was obtained from improved variety under improved management practice while the lowest net benefit was obtained from the local cultivar under farmer's management practice (Table 4). Accordingly, the highest economic benefit was recorded for improved variety under improved agronomic management practice.

Implementation of the recommended agronomic management practices improves the productivity of crops with quality. Crop management practice is the set of agricultural practices applied to improve the growth, development, and yield of crops. Improved rice variety under improved agronomic management practices had given higher grain yield as compared to same varieties under farmer's practice. In addition to this, the local cultivar also showed better yield performance as compared to farmer’s practices under improved agronomic management practices. On the other hand, the improved variety had given the lowest yield even from the local cultivar under farmer's practice. This indicates that improved variety alone cannot give the expected yield if the other production packages are not properly applied. The yield advantage of 43.9% and 24.5% was recorded with improved variety and local cultivar, respectively when grown under improved agronomic management practices over farmer's practice. As a whole, the combined result indicated that growing improved variety together with recommended agronomic management practices can increase the yield up to 4516 Kg ha^-1. Thus, creating awareness and increasing access to the use of improved varieties and full technology packages considering the fertility status of the soil is crucial to enhancing productivity and also closing yield gaps. The use of fertilizer with proper crop management is particularly important for realizing the genetic potential of improved varieties.

Acknowledgments
I am thankful to South Agricultural Research Institute (SARI) and Bonga Agricultural Research Center for their financial support.