Embrapa Clima Temperado Research Articles

Indicadores biológicos de qualidade do solo de fácil obtenção para o monitoramento do cultivo de milho com base agroecológica

ABSTRACT The soil is a natural resource of biotic and abiotic combinations affected by management and may significantly change their functionality. This study evaluates the impact of agricultural practices adopted under ecologically based management on corn cultivation compared with an adjacent native forest area. The study was developed in the experimental areas and laboratories of the Cascata Experimental Station - Embrapa Clima Temperado, Pelotas/ RS. The diversity of edaphic fauna was obtained by the PROVID method, which resulted in similarity in both environments. It was observed that the Shannon diversity index and Pielou equitability index were significantly higher in corn cultivation. Compared to Renyi's diversity profile, the edaphic fauna in corn presented a higher index of species than in the native forest (α<2), attributed to a greater source of food for some communities. The bait-lamina methodology was used for the feeding activity of the soil biota, evidencing an average activity in corn approximately 60% higher compared to the forest (48.14%). These indexes must be associated with the average content of OM present in the soil, being 6.04% in the forest and 2.39% in the corn, because when analyzed by the T-test, they present significant levels for the feeding activity. It is concluded that the assessment of the impact of agricultural practices adopted under ecologically based management in corn cultivation resulted in no significant difference when compared with the adjacent native forest area since levels of similarity between the environments were identified concerning biological parameters of the soil.

Growth of pecan rootstocks with the use of liquid humus in an organic production system

Pecan farming is a long-term investment which needs quality seedlings to establish an orchard. Pecan rootstocksmust have a vigorous radicular system to form quality seedlings. Liquid humus, which acts as an agent thatpromotes their growth and development, is a bioinput that is specially used in organic production systems.This study aimed at evaluating effects of different frequencies of liquid humus application on pecan rootstockgrowth and development in an organic system. Liquid humus at 30% was applied every 7, 14, 21 and 28 days.The control treatment consisted of water application. The experiment was carried out with ‘Barton’ rootstocksin a greenhouse at the Embrapa Clima Temperado located in Pelotas, RS, Brazil. The following variables wereevaluated 280 and 480 days after transplantation: plant height; stem diameter; leaf area; fresh and dry massesof the aerial part; main and secondary root lengths; fresh and dry masses of roots; fresh and dry masses of themain root; fresh and dry masses of secondary roots; and the Dickson Quality Index. Liquid humus increasedsecondary root length of pecan rootstocks, mainly when it was applied every seven days. Thus, the bioinputmay be used for this purpose.

Genetic trends and multivariate interrelationships for grain quality of irrigated rice genotypes

For genetic improvement programs, researches with multivariate approaches in rice are fundamental, to define genetic trends, clusters and correlations of agronomic characters that together help selection procedures. This work aimed to reveal the agronomic performance, trends and genetic interrelationships of grain quality based on multivariate models applied to elite lines of irrigated rice. The experiment took place in the 2017/2018 harvest, held at Estação Experimental Terras Baixas (ETB), of Embrapa Clima Temperado. The study used randomized blocks design, with three replications. There were fifteen F6 lines and four control cultivars. Evaluation of intrinsic physical quality attributes with the aid of S21 grain statistical analyzer, as well as grain yield and mill yield (whole and broken grains). Performance of analysis of variance, genetic parameters and Scott Knott cluster test, linear correlation, canonical correlations, cluster analysis via generalized Mahalanobis distance, using the Toucher method, in addition to BIPLOT principal component analysis. The results showed that PH18502 and PH18701 strains presented better agronomic performance for the studied characters, by univariate analysis. The linear and canonical correlations presented demonstrate potential in the direction of selection of multiple characters and point to the possibility of indirect selection among the relevant agronomic characters for the production chain of irrigated rice.

‘BRS F50’ (Cecília): Cultivar de batata multiuso com resistência a doenças foliares

ABSTRACT ‘BRS F50’ (Cecilia) is a yellow skin potato cultivar for the fresh market, with good tuber appearance and versatile culinary use. The tuber has oval shape, shallow eyes, and light yellow flesh. It has a relatively high dry matter and medium-low glucose content, giving possibility even to use for processing into shoestring fries. The vegetative cycle and dormancy are medium. The maturity and tuber dormancy are medium. ‘BRS F50’ (Cecilia) shows a very low external and internal tuber disorder incidence, except growing cracks under varying soil humidity. It is moderately resistant to late and early blight, which make it also suitable for organic production. ‘BRS F50’ (Cecilia) was released by Embrapa in 2022, and is a product of its potato breeding program, developed by Embrapa Clima Temperado, in Pelotas-RS and Canoinhas-SC, and Embrapa Hortaliças, in Brasília-DF, Brazil.

Progresso genético em 53 anos do Programa de Melhoramento de pessegueiro da Embrapa: cultivares para consumo fresco

Abstract A peach breeding program started in 1963, at the Experiment Station of Pelotas, nowadays Embrapa Clima Temperado, whose primary aim was developing cultivars adapted to mild winter conditions. Its first priority was to obtain cultivars of canning type fruits, and over the years, the fresh market cultivars acquired equal importance. This article analyzes the data of 84 fresh market cultivars, obtained in Pelotas, from 1964 to 2017, focusing on the following parameters: time of ripening, fruit development period, average fruit mass, number of fruits per tree, productivity per plant and total soluble solids. First, the data were tabulated, divided into two periods (1964-1984 and 1985-2017), and the descriptive statistical analysis was performed, followed by an analysis via mixed models and estimates of genetic progress via meta-analysis. The main results revealed a reduced fruit development period of the fresh market peaches belonging to that program. It was also observed a significant spread of the time of ripening (end of September or beginning of October until January), with a slight tendency for earliness. Genetic gain was observed for yield corresponding to 1.17 and 2.25% per year, for 1964-1984 and 1985-2017, respectively.

Number of days to reach the main plant developmental stages of irrigated rice cultivars

The objective of this study was to determine the number of days (ND) to reach the main plant developmental stages (PDS) of irrigated rice cultivars. Field experiments were carried out at the Estação Experimental Terras Baixas (ETB) of Embrapa Clima Temperado, located in the municipality of Capão do Leão, State of Rio Grande do Sul, Brazil, during 12 crop seasons, using six sowing dates in each. Ten plants from each cultivar were tagged and had each of the PDS monitored throughout the crop cycle. The results indicated that the ND to reach each of the six PDS varied according to the cycle of the cultivars and that there was statistical difference between some of them. The ND to reach the stages R1 (panicle differentiation), R4 (anthesis) and R9 (complete panicle maturity) of the cultivar IRGA 424, for example, were 63, 96 and 125, respectively. The average number of days to reach the different plant developmental stages varies according to the cycle length of the cultivars, and the subperiod of longer duration is that between the four-leaf and panicle differentiation stages (V4-R1).

Accumulated degree-days to reach the main plant developmental stages of irrigated rice cultivars

The objective of this study was to determine the accumulated degree-days (DD) to reach six plant developmental stages (PDS) of irrigated rice cultivars. Field experiments were carried out at the Estação Experimental Terras Baixas (ETB) of Embrapa Clima Temperado, located in the municipality of Capão do Leão, State of Rio Grande do Sul, Brazil, during 12 crop seasons, using six sowing dates in each. Ten plants of each cultivar were tagged and had each of the PDS monitored throughout the crop cycle. The DD (°C day) were calculated as the sum of the daily values resulting from the difference between mean air temperature (Tm) and the minimal base temperature (Tb = 11 °C), from the emergence until the date of each PDS. The results indicated that the DD to reach anthesis (R4) represented, in the average, about 77% of the total cycle (R9), ranging from 73% for IRGA 421 to 91% for Epagri 109. The vegetative period (from E-emergence to R1) is the one with the highest average DD value, around 48% of the total cycle, presenting also the largest differences between cultivars when compared to the reproductive period 1 (R1-R4) and the reproductive period 2 (R4-R9).

Overcoming dormancy in citrus rootstock seeds

Citrus is a fruit of great importance in Brazil, mainly in the socio-economic issue as it generates employment and income due to the production and export of concentrated orange juice, as well as other products. In view of the above, this work aimed to evaluate the dormancy overcoming of citrus seeds of the cultivars: Flying Dragon, San Diego, Índio, Cravo Santa Cruz, Riverside, BRS Sunki Tropical, Volkamerian, as well as the species Poncirus trifoliata. The seeds from Embrapa (Brazilian Agricultural Research Corporation) Clima Temperado, located in Pelotas-RS, as well as from Embrapa Cassava e Fruticultura, located in Cruz das Almas-BA, were submitted to the germination test as written in the Seed Analysis Rules and a germination test in which a small cut was made in the seed coat on the side of the embryo, around 0.1 mm with the help of a stylet, which was used 200 seeds (4 samples of 50 seeds per repetition) on germitest® paper, moistened with distilled water in an amount equivalent to 2.5 times its weight and kept inside a germinator at a constant temperature of 25 °C, photoperiod of 12 hours. The evaluations were carried out at the end of the 21 days after the installation of the test, providing data that were expressed in percentage of normal and abnormal seedlings and non-germinated seeds (hard, dormant or dead). of citrus seedlings at the end of the tests and the data obtained were submitted to analysis of variance and the means were compared by the Tukey test at a 5% significance level (p≤0.05), with the aid of the R- bio. It is concluded that, when evaluating germination and shoot and root length of seedlings cultivars Flying Dragon, Índio, Cravo Santa Cruz, BRS Sunki Tropical, Riverside and Volkameriano, San Diego and the species P. trifoliata, were satisfactory when submitted in the dormancy breaking process, but further studies are needed.

Carryover of [imazapic + imazapyr] on differents crops systems in lowland areas with ALS tolerant rice

This study aimed to assess the impact of the herbicide associated to the Clearfield® technology of rice cultivation on ryegrass planted in succession, as well as on both non?Clearfield® rice and soybean planted in rotation. Was installed in the Lowlands Experimental Field, Embrapa Clima Temperado, Capão do Leão, Brazil, from 2016 to 2018. The experiment comprised the application of Kifix® (imazapic + imazapyr) to Clearfield® rice grown at the first experimental year, evaluating its impact on the Clearfield® rice (1st summer), on ryegrass grown on the succeeding winter, as well as on soybean and non?Clearfield® rice grown on the following summer cropping season (2nd summer). The randomized blocks design was used with four replications, with plots measuring 72 m2 at the first cropping season and winter cropping, being later split (32 m2) for the second summer cropping season, to allow planting both non?Clearfield® rice and soybean. Our experiments reported mild damages from Kifix® residues on ryegrass planted in succession to Clearfield® rice, as well as on non?tolerant rice and soybean in rotation to Clearfield® rice, under lowland areas of Southern Brazil. Furthermore, the possibility of accumulation of Kifix® residues in soil, after repeated applications should be verified in further studies.

Bioactive compounds and physical-chemical characteristics of two genotypes of peach trees submitted to nitrogen fertilization

Nitrogen, which is the primary nutrient peach trees need, may affect their fruit quality. Thus, this study aimed at evaluating the effect of nitrogen fertilization on two genotypes of peach trees, regarding their fruit quality, in three consecutive crops. The experiment was carried out in the experimental area that belongs to the Embrapa Clima Temperado, located in Pelotas, Rio Grande do Sul (RS), Brazil, from 2016, 2016, 2017 and 2018. Four doses of nitrogen (0, 60, 120 and 180 Kg ha-1) and two peach tree genotypes (‘Cascata 1513’ and ‘Cascata 1067’) were used. For the fruit, we evaluated epidermis color, pulp firmness, epidermis firmness, soluble solids concentration, titratable acidity, concentration of total phenolic compounds, anthocyanins and antioxidant activity. Fruit underwent physical, chemical and bioactive compound analyses. Results showed that the highest dose of nitrogen (180 Kg ha-1) applied to the soil retards fruit ripening, while no application of nitrogen fertilization brings fruit maturation forward. Nitrogen fertilization via soil does not favor anthocyanins in fruit. Doses of 60 and 120 Kg ha-1 of nitrogen are recommended because they lead to improvement in peach color, epidermis firmness and acidity. Peach tree genotypes influence soluble solids, juice pH, phenolic compounds and antioxidant activity of their fruit.

Intraspecific competition of hybrids using mixtures of pollinator lines for hybrid rice production

The aim of this study was to evaluate the use of pollinator seed mixture to obtain hybrid rice seeds. The study was performed at Embrapa Clima Temperado, in the harvests of 2015/2016 and 2016/2017. Seeds of hybrids H7 and BRS AH 703 CL and the pollinator, Puitá INTA-CL cultivar were used in the proportions of 0.00%, 0.75%, 1.50%, 3.00%, 6.00%, 12.00% and 24.00% in the first year and 0.00%, 0.75%, 1.50%, 3.00%, 6.00%, 12.00% and 24.00%, 50.00% and 100.00% for the second year. The experimental design was a randomized complete block design with four repetitions and the data was submitted to analysis of variance. Seeding was performed in November and October. The plots were 5 meters long with 4 meters of plot area, being evaluated: Number of plants.m-2, Number of culms.m-2, Number of panicles.m-2, Panicle length, Productivity of grain, plot uniformity, plant height, percentage of whole grains, broken grains. Plants from hybrid rice seeds in the mix had no effect on yield components. Plants from hybrid seeds showed plot uniformity like plants from self-fertilization. The industrial quality of the grains was like grains of self-fertilized plants but differing in the intermediate mixtures used.

Poda de raízes de porta-enxertos de nogueira-pecã em diferentes recipientes

Abstract Quality pecan rootstocks that ensure genetic and phytosanitary safety, besides having good vegetative development, are extremely important to implant a successful orchard. Rootstocks with vigorous radicular systems affect plant growth. This study aimed at evaluating rootstock growth as the result of root pruning and the use of different containers to grow pecan rootstocks in an organic system. The experiment was conducted with “Barton” rootstocks in the experimental area at the Embrapa Clima Temperado in Pelotas, RS, Brazil, in 2018, 2019 and 2020. Rootstocks were evaluated in plastic bags and tubes and in the soil, associated with root pruning. Evaluation 280 and 480 days after transplant comprised the following: height of the aerial part, length of primary and secondary radicular systems, stem diameter, leaf area, dry mass of the aerial part, dry mass of the radicular system, dry mass of secondary roots and the Dickson Quality Index. The use of plastic bags to produce pecan rootstocks was found to coil roots at the bottom of the container. Neither containers nor root pruning affected stem diameter, an important parameter to carry out grafting. Pecan rootstocks with a non-pruned radicular system grown in plastic bags developed large main root and aerial part. Pruning of pecan radicular systems in containers and in the soil leads to increase in the number of main roots but decreases root length.

Peach Tree Short Life in Rio Grande do Sul State, Brazil

The Peach Tree Short Life (PTSL) is a syndrome that causes severe damage to peach trees, usually between one and eight-years-old, which can lead to the scion death. In Brazil, it has importance mainly in the Rio Grande do Sul State, which is the largest Brazilian peach producer. First reported in the Pelotas area, in late 1970s, the syndrome continues to cause damage, with varying intensities among years. Several causes have been reported in national and international literature, involving biotic and abiotic factors. In Rio Grande do Sul, due to the predominant use of mixtures of scion peach pits from canning industry for rootstock production, it is not possible to know varietal identity of tree root system in commercial orchards. This genetic variability which causes heterogeneity among trees, can at the same time under the environmental selection pressure, be used in a clonal selection program in situ, in search for tolerant sources. In another strategy developed by Embrapa Clima Temperado, evaluation of cultivars, species and interspecific hybrids as rootstocks are also underway. In the present paper, we report main technical and scientific advances on PTSL in Rio Grande do Sul and the focus on search for tolerant rootstocks and quality of nursery trees.

A agrobiodiversidade e seu papel em relação à variabilidade e aos recursos genéticos em pimenta <i>Capsicum chinense</i>

Nas últimas décadas, a biodiversidade vem passando por um processo de degradação sem precedentes na história humana, por causa de um modelo superado de exploração. A agrobiodiversidade faz parte da biodiversidade, mas tem uma visão contrária àquele modelo, ao buscar interagir com os inúmeros ecossistemas e formas de produção. As pimentas, conhecidas mundialmente entre as especiarias picantes, e importante componente da agrobiodiversidade do nosso país, vêm sendo substituídas por outras opções de cultivo. Visando à conservação da diversidade genética das pimentas no Sul do Brasil, a Embrapa Clima Temperado mantém, desde 2002, um Banco Ativo de Germoplasma (BAG) de pimentas do gênero Capsicum. O objetivo do trabalho foi descrever a variabilidade genética de frutos de pimenta da espécie Capsicum chinense, como forma de documentação para o Banco Ativo de Germoplasma (BAG) da Embrapa Clima Temperado. Para isso, 11 acessos de pimenta do BAG de Capsicum da Embrapa Clima Temperado foram caracterizados, utilizando-se descritores morfológicos recomendados pelo International Plant Genetic Resources Institute.

Feijão-sopinha: ideótipo de leguminosa de múltiplo propósito de alto valor nutricional

O objetivo deste trabalho foi avaliar o potencial do feijão-sopinha, uma cultivar crioula de caupi [Vigna unguiculata (L.) Walp.], como planta de multipropósito, para sua utilização como forrageira, cobertura do solo e produção de grãos. A identificação de plantas de múltiplo propósito para a diversificação dos sistemas de produção é essencial para atingir uma agricultura sustentável. O feijão-miúdo (ou caupi) enquadra-se nesse conceito, pois é utilizado como planta de cobertura de solo, adubação verde e produção de forragem e de grãos. A Embrapa Clima Temperado possui uma coleção com mais de 20 acessos de feijão-sopinha, coletados em toda a região de clima temperado. Os estudos foram realizados na Estação de Terras Baixas, em Capão do Leão, RS, em um Planossolo de baixa fertilidade. Os experimentos consistiram da caracterização agronômica da planta e da avaliação da produção de forragem e de sementes e de suas qualidades nutricionais. Na forragem e nos grãos, analisaram-se os seguintes parâmetros: conteúdo de fibras, proteína total, lignina e matéria mineral. Nos grãos, analisaram-se, ainda, os teores de antocianinas, carotenoides, polifenóis e atividade antioxidante total. O feijão-sopinha apresenta ciclo mais longo do que o feijão-miúdo e é capaz de produzir 9,2 Mg ha-1 de massa de matéria seca, com um único corte na fase de floração das plantas. A forragem de feijão-sopinha apresenta boa qualidade quanto à composição de fibras e proteína total. O feijão-sopinha tem potencial para seu uso como planta forrageira, cobertura de solo e produção de grãos e, portanto, serve como ideótipo como planta de múltiplo propósito.

Performance of soybean cultivars in integrated pest management in lowland agroecosystem

Soybean crop represents a large economic share in the Brazilian agricultural production. In Rio Grande do Sul (RS), with each new crop cycle there is an increase in the area under cultivation. In the lowland environment, the crop covers 5.4 million hectares, corresponding to about 20% of the State total area. Using transgenic cultivars whose main advantage is controlling target insects, as well as the reduced number of insecticide applications throughout the crop can be a viable alternative. However, the high cost of transgenic seed is considered as the main disadvantage in adopting this technology. The objective of this study was to evaluate the performance of cultivars RR1 and RR2 in relation to the occurrence of caterpillars and stink bugs, as well as to evaluate the production cost. The experiment was set up at Embrapa Clima Temperado in the crop seasons of 2014/2015 and 2015/2016, with conventional cultivars (BMX Potencia (RR1 6.7)) and Bt isolines (BMX Ponta (IPRO 6.6)) and BMX Vanguarda (IPRO 6.0)). BMX Potencia cultivar showed a higher incidence of defoliating caterpillars and Nezara viridula stinkbug, but it is the most indicated cultivar, among those evaluated, for the south lowland environment of RS, due to its yield and profitability.

Field behavior of potted seedlings of strawberry plants in different growing seasons

Since dependence on seedling importation has been a hindrance to strawberry farmers, production of national plants has become an alternative solution. This study aimed at evaluating the field behavior of potted seedlings of strawberry plants in a low tunnel system in different early growing seasons in Rio Grande do Sul, Brazil. The experiment was carried out at Embrapa Clima Temperado in 2015 and 2016 in a randomized block design, composed of a 4x3 factorial, four cultivars (Aromas, Camarosa, Festival and Oso Grande) and three growing seasons (March 16th, April 1st and April 16th). For all seasons, the cultivation was until November 30 in 2015 and October 31 in 2016. The following variables were determined: beginning and full blooming, beginning and length of harvest; number of fruits; mean fruit mass; and fresh mass per plant throughout early and total production. The cultivar Aromas presents lower flowering uniformity among plants (difference between beginning and full flowering) according to the two years of evaluation. Potted strawberry seedlings planted until early April 1st - Season 2 in Pelotas, RS, allow high early production, with production above 400 grams per plant. The cultivar Camarosa when planted on March 16 or April 1 had total yield per plant above 800 grams. All cultivars under study (Aromas, Camarosa, Festival and Oso Grande) have better plant development and higher total yield gains in years with higher temperature and lower rainfall in the initial phase and good rainfall distribution over the growing season. (2015) than in years with most frequent precipitation and lower temperature in the initial phase and poor rainfall distribution over the growing season (2016).

Sprinkler irrigation in lowland rice: Crop yield and its components as a function of water availability in different phenological phases

Efficient water use in agriculture is a global demand, and in this context, the implementation of a sprinkler irrigated rice system has become a reality. Besides saving water, proper management of a sprinkler irrigated system can maintain high levels of productivity. This study aimed to determine the effect of soil water tension on rice crop production, in both vegetative and reproductive stages, as well as to evaluate the effect of soil water availability and physicochemical attributes on biometric and reproductive characteristics associated to rice grain yield under sprinkler irrigation. The experiment was carried out at the Lowland Experimental Station, Embrapa Clima Temperado, Capão do Leão – Rio Grande do Sul, Brazil, during two growing seasons, in an area irrigated by a lateral-move sprinkler irrigation system. The following irrigation managements were evaluated: irrigation, when the mean soil water tension was i) 10 kPa; ii) 20 kPa; iii) 40 kPa; iv) 40 kPa on vegetative and 20 kPa on reproductive stages and v) 40 kPa on vegetative and 10 kPa on reproductive stages. Under sprinkler irrigation, rice plant development was impaired as soil water tension increased, evidenced by a reduction in plant heights. Soil water tension of 10 kPa was adequate to manage the sprinkler irrigation in rice, especially in the reproductive stage and when using cultivars developed for flooded environments. Rice development and yield were affected by increasing soil bulk density and acidity. Rainwater represented approximately 40 % of the water used by sprinkler irrigated rice during the crop cycle, contributing with the reduction of irrigation water use.

Características físico-hídricas de substratos formulados com lodo de esgoto na produção de mudas de acácia-negra

Avaliou-se o efeito da retenção de água de substratos para plantas formulados a partir de diferentes proporções de lodo de esgoto (LETE) solarizado, na produção de mudas de acácia-negra (Acacia mearnsii). O experimento foi conduzido em casa de vegetação e no Laboratório de Física do Solo da Embrapa Clima Temperado. O LETE utilizado foi coletado em leitos de secagem de uma Estação de Tratamento de Esgoto aeróbio de Rio Grande - RS. Os tratamentos consistiram de cinco doses de LETE solarizado, combinadas com cinza de casca de arroz e vermiculita em diferentes proporções (20:40:40, 30:35:35, 40:30:30, 50:25:25 e 60:20:20) e dois substratos comerciais (Beifort® S10 B e Mec Plant®). O delineamento experimental foi de blocos casualizados. Foram avaliadas as características físico-hídricas: água facilmente disponível, água tamponante, água remanescente e capacidade de retenção de água. As variáveis de crescimento avaliadas foram: massa fresca da parte aérea e do sistema radicular. O substrato com 20% de LETE solarizado, 40% vermiculita e 40% cinza de casca de arroz apresentou a melhor condição físico-hídrica para o desenvolvimento de mudas de acácia-negra.

Correlations and path analysis for yield components in irrigated rice

Grain yield of irrigated rice is a complex character resulting from the expression and association of different components, which should be considered by the breeder for an efficient process of selection of new genotypes. In this sense, the objective is to highlight the phenotypic correlations and the direct and indirect associations of the main components related to crop yield via path analysis. The experiment was carried out in an experimental field of the Lowlands Station of Embrapa Clima Temperado using six genotypes of irrigated rice: the cultivars BRS Pampa, BRS IRGA 409, BRS 7 ‘Taim’, BRS Sinuelo CL, BRS Pampeira and AB 10101 CL. The agronomic characters evaluated were grain yield, days to flowering, panicle length, panicle mass, number of fertile spikelets, number of sterile spikelets, number of tillers per plant, number of panicles per square meter, and mass of one thousand grains. The number of fertile spikelets, number of panicles per square meter, panicle mass and mass of one thousand grains influenced grain yield, both through phenotypic correlation and direct effects. In addition, there was a high direct linear tendency of these variables towards yield. Panicle length and number of sterile spikelets showed a potential of use in the indirect selection for grain yield.