Lindomar Maria da Silveira

Desempenho agronômico do bicultivo da alface em sistemas consorciados com cenoura em faixa sob diferentes densidades populacionais

The experiment was carried out from June to September 2003, in the field, in Mossoro, Rio Grande do Norte State, Brazil, to evaluate the lettuce bicropping agronomic performance in intercropping systems with carrot in a strip arrangement under different planting densities of component crops. The experimental design used was of randomized complete blocks in a 4x4 factorial scheme with five replications. The treatments of the factorial consisted of the combination of four lettuce-planting densities [40%, 60%, 80% and 100% of the recommended sole crop density (RSCD)] with four carrot-planting densities (40%, 60%, 80% and 100% of the RSCD). The recommended planting densities for lettuce and carrot in sole crop were of 250.000 and 500.000 plants/ha, respectively. The planted lettuce and carrot cultivars were respectively: Taina and Brasilia. Evaluations of plant height and diameter, number of leaves and fresh weight per plant, shoot dry mass, and leaf productivity were made in the lettuce crop. In the carrot crop, total and commercial yields of roots were evaluated. There was no significant interaction between lettuce densities and carrot densities in any assessed trait of both crops. In the first lettuce growing, the increase of planting density increased significantly lettuce leaf yield and decreased plant height and fresh mass per plant. Increasing in the association of planting densities of both crops increased shoot dry mass of lettuce. In the second lettuce growing, the increase of planting density increased significantly plant height, leaf productivity and shoot dry mass, besides decreasing fresh mass per plant. As the association of carrot and lettuce planting densities increased, the total and commercial yield of roots increased.

Associação de densidades populacionais de cenoura e alface no desempenho agronômico da cenoura em cultivo consorciado em faixa

An experiment was carried out from June to September 2003, in the field, in Mossoro, Rio Grande do Norte State, Brazil. Associations of carrot (cv. Brasilia) and lettuce (cv. Taina) planting densities on carrot agronomic performance in strip-intercropping system were evaluated. The experimental design was of randomized complete blocks in a 4 x 4 factorial scheme with five replications. The treatments of the factorial consisted of the combination of four carrot-planting densities [100%; 80%; 60% and 40% of the recommended sole crop density (RSCD)] with four lettuce-planting densities (100%; 80%; 60% and 40% of the RSCD). The recommended planting density for the sole crop in the region is of 500.000 plants/ha for carrot and 250.000 plants/ha for lettuce. From the carrot crop we evaluated the plant height, shoot and root dry mass, total and commercial yield and classification of roots. No significant interaction between carrot densities and lettuce densities for any assessed trait in carrot crop was obtained. Also, no significant effect of increase in lettuce density was observed for any carrot-assessed trait. Plant height increased as carrot planting density increased, whereas shoot and root dry mass, and percentage of long and mean, and refused roots decreased with increasing of carrot density. As the association of carrot and lettuce planting densities increased, the total and commercial yield and percentage of short roots increased.

Qualidade de raízes de cenoura em sistemas consorciados com alface sob diferentes densidades populacionais

The experiment was carried out from June to September 2003, in Mossoro, Rio Grande do Norte State, Brazil, to evaluate the quality of carrot roots (cv. Brasilia) in intercropped systems with lettuce (cv. Taina) under different planting densities. The experimental design used was of randomized blocks in a 4 x 4 factorial scheme with three replications. The treatments consisted of the combination of four carrot-planting densities [(40%, 60%, 80% and 100% of the recommended sole crop density (RSCD)] with four lettuce-planting densities (40%, 60%, 80% and 100% of RSCD). The evaluated quality characteristics of the carrot roots were: titrable total acidity (TTA), total soluble solids (TSS), total sugars (TSU), pH, and TSS/TSS ratio, besides commercial productivity of carrot roots and lettuce yield. There was a significant interaction between carrot planting-densities and lettuce-planting densities on TSS of carrot roots. The TTS content and pH increased with increasing carrot-planting densities. Commercial productivity of carrot roots and lettuce yield also increased with increasing in planting densities. The variation in the carrot planting density did not influence lettuce yield but the variation in the lettuce planting density negatively influenced commercial productivity of carrot roots. Among the assessed characteristics, TSS and TSS were significantly correlated with commercial productivity, showing that these traits may be representative of carrot root quality.

Emergência e desenvolvimento de mudas de tomate IPA 6 em substratos, contendo esterco ovino

The search for alternative substrat that can replace commercial products in the tomato seedlings production is very important to reduce costs at the first stage of such culture. The present study aimed to evaluate the quality of industrial tomato IPA 6 seedlings produced with alternative substrate of sheep manure. The experiment was carried ou at a plant nursery at the Universidade Federal Rural de Pernambuco, in Serra Talhada, Pernambuco State, Brazil, from February 16 to March 30, 2012. The experimental design was a completely randomized design with four replications. The treatments were: T1 - commercial substrate; T2 - sheep manure + sand (1:1); T3 - sheep manure + sand (2:1); T4 - sheep manure + sand (3:1); T5 - sheep manure + soil (1:1); T6 - sheep manure + soil (2:1); T7 - sheep manure + soil (3:1); T8 - sheep manure + sand + soil (1:1:1); T9 - sheep manure + sand + soil (2:1:1); T10 - sheep manure + sand + soil (3:1:1). The emergence indicators were: percentage, speed index and average time of emergence. Regarding the development characteristics of seedlings were analyzed: leaf number, stem diameter, seedling height, root length, shoot dry matter and root dry matter. The commercial substrate provided better vigor of tomato IPA 6 seedlings. Moreover, the use of soil and sheep manure (2:1) to compose alternative substrates consisted of a viable option for seedlings production of this cultivar.

Seleção de acessos e progênies de Citrullus spp. para resistência a três potyvirus

Six watermelon (Citrullus spp.) accessions (87-019, 87-029, 91-080, PI-244018, 91-043 and PI-195927) and two samples (PI-244019A and PI-244019B) from the acession PI-244019B from Embrapa Cucurbit Germplasm Bank in Petrolina-PE, Northeast of Brazil were evaluated in an attempt to select accessions and progenies of watermelon as sources of resistance to Papaya ringspot virus type watermelon (PRSV-W), Watermelon mosaic virus (WMV) and Zucchini yellow mosaic virus (ZYMV). Endogamic and open pollinated progenies from these accessions were also evaluated for resistance to PRSV-W, WMV and ZYMV. The evaluations were carried out in a greenhouse at the Plant Virus Laboratory of the Federal University of Ceara where the plants were mechanically inoculated and serological screened by Elisa. The selected plants were grown in the Experimental Station of Bebedouro in Petrolina-PE, where the virus inoculations were made, naturally, by vectors. According to the results, plants were not infected by PRSV-W in the following accessions: 87-019, PI-244019A, 91-080, PI-244018, PI-244019B and PI-195927; plants were not infected by WMV in the accessions: 87-019 and 87-029; and plants were not infected by ZYMV in the accessions: PI-244019A, 87-029, 91-080,91-043, PI-244019B and PI-195927. The progenies showed differentiated behavior with the percentage of selected plants ranging from 20 to 100% for PRSV-W and 60 to 100% for WMV. The progenies evaluated against ZYMV did not show resistant plants. Therefore, it can be postulated that resistance for PRSV-W and WMV in the progenies differs from that for ZYMV, since all progenies were submitted to the same number of self-pollinations.

Agronomic performance of carrot fertilized with roostertree [Calotropis procera (Ait.) R. BR.] in two growing seasons

Because vegetables have a fast production cycle, they require fertilization in quantities and at ideal times to obtain maximum productivity, and green manure is an alternative practice to the use of mineral fertilizers. This study was conducted to evaluate the effects of different amounts of roostertree [Calotropis procera (Ait.) R. Br.] biomass and its incorporation times in two growing seasons, in the agronomic performance of carrots. The experiment was conducted on an experimental farm at the Universidade Federal Rural de Pernambuco (UFRPE) in the autumn-winter period (March-July 2012) and the spring-summer period (September-December 2012). The experimental design was a randomized block design with three replications. The treatments were arranged in a factorial 4 x 4 design; the first factor consists of four amounts of roostertree biomass (5.4, 8.8, 12.2 and 15.6 t ha on a dry basis), and the second factor consists of four times of incorporation of this manure into the soil (0, 10, 20 and 30 days before sowing the carrots). The carrot cultivar used was Brasília. The following traits were evaluated: plant height, number of leaves per plant, root dry mass, total and commercial yield of roots. The best agronomic performance of carrot cultivar Brasília was found with the amount of roostertree biomass of 15.6 t ha, in the time of incorporation into the soil of 10 days before seeding. The cultivation in the autumn-winter showed higher total and commercial productivities of carrot roots fertilized with roostertree.