Effect of Sowing Dates and Varieties on Growth and Yield of Broccoli under Acidic Soil Condition of Sylhet

This experiment was conducted during October, 2013 to March, 2014 in the experimental field of Department of Horticulture, Sylhet Agricultural University (SAU), Bangladesh. The objective was to evaluate the effect of three planting dates (30 October, 15 November and 1 December) on growth, yield and yield attributes of three broccoli varieties (Premium, BR001 and BR002) under acidic soil condition of Sylhet. The two factors field experiment was laid out in Randomized Complete Block Design (RCBD) with three replications. Broccoli planted on 30 October recorded the minimum number of days to first curd harvest (64.77), the tallest plants at harvest (62.76 cm) with denser leaves (17.90), the highest primary curd weight (142.75 g) with increased curd length (11.93 cm), the maximum curd yield of both primary (5.29 t/ha) and secondary (5.24 t/ha). Variety Premium was the earliest in curd initiation (50.33 days) and curd harvest (64.44 days). Premium had the highest number of leaves at harvest (16.07), the maximum primary curd weight (207.59 g) with increased curd length (12.18 cm) and curd diameter (14.28 cm). The highest primary curd yield (7.70 t/ha) and secondary curd yield (4.02 t/ha) of Premium variety out yielded the other two varieties in this experiment. Interaction effect showed that the variety Premium planted on 30 October showed the best performance in primary curd weight (274.13 g), primary curd yield (10.17 t/ha) and secondary curd yield (8.43 t/ha). Therefore, the variety Premium can be recommended to cultivate at 30 October planting date under acidic soil condition of Sylhet.

Corn (Zea mays L.) growth, nutrient uptake and soil fertility improvement of strongly acidic soil applied with biochar and animal manure

The effects of biochar and animal manure application on soil chemical properties, nutrient uptake, growth, andbiomass production of corn grown in strongly acidic soil were assessed in a pot experiment. The experimentwas laid out in randomized complete block design with the following treatments: (1) control; (2) 15 t chickenmanure (CM) ha−1; (3) 30 t CM ha−1; (4) 15 t carabao dung (CD) ha−1; (5) 30 t CD ha−1; (6) 15 t chickenmanure biochar (CMB) ha−1; (7) 30 t CMB ha−1; (8) 15 t carabao dung biochar (CDB) ha−1; and (9) 30 tCDB ha−1. Application of 30 t CM ha−1 significantly increased soil pH by 1.03-unit, total organic carbon,total N, and exchangeable K by 138%, 300%, and 955%, respectively, and a 108-fold increase in P, over thecontrol treatment. Similarly, the addition of CM at 15 t ha−1 significantly increased all soil chemical parametersgathered. Moreover, the addition of 15 t CM ha−1 increased plant height, shoot, and total biomass by 62%,161%, and 148% over the control treatment. Meanwhile, tissue N uptake of corn increased by 147% and 124%with the CM application at the rate of 15 t ha−1 and 30 t ha−1. Among organic materials evaluated, CM had themost superior influence on soil chemical properties, growth, biomass production, and plant nutrition.

Tolerance evaluation of Jatropha curcas and Acacia burkei to acidic and copper/nickel-contaminated soil

Aim: To evaluate tolerance of two tree species, Jatropha curcas and Acacia burkei, to an acidic and highly Cu/Ni-contaminated soil. Methodology: Above-ground growth of Jatropha and Acacia were monitored for six months in two different soil types; a typical field soil (FS) and acidic and Cu/Ni-rich soil (ACNS), the latter containing 58- and 14-fold higher levels of Cu and Ni, respectively, than FS. Results: Growth of Acacia was markedly inhibited in ACNS, as evidenced by low number of petioles and branches, thinner stem diameter, and low chlorophyll content compared with plants grown in FS. In contrast, tree height, stem diameter and length of emerged branches of Jatropha showed no significant differences between growth in FS and ACNS. In Jatropha, foliar Cu content grown in ACNS was not statistically different from that in FS whereas a small increase in foliar Ni content was observed in ACNS. Interpretation: These observations suggested that Jatropha possess strong resistance to acidic and Cu/Ni-enriched soil. This trait might be advantageous for dual-purpose, utilization of Jatropha for renewable energy production and afforestation of Cu/Ni-polluted wastelands.

Plant-enhanced phenanthrene and pyrene biodegradation in acidic soil.

A study was undertaken to assess if corn plant (Zea may L.) may be able to enhance the degradation of phenanthrene and pyrene in acidic soil inoculated with a bacterial strain (Pseudomonas putida MUB1) capable of degrading polycyclic aromatic hydrocarbons (PAHs). Planting with corn, inoculating with MUB1, or a combination of the two were found to promote the degradation of phenanthrene and pyrene in acidic soil at different rates. In the presence of corn plants, the rates of phenanthrene and pyrene removal were 41.7 and 38.8% in the first 10 days, while the rates were 58.8 and 53.6%, respectively, in the treatment which received MUB1 only. After 60 days, the corn + MUB1 treatment led to the greatest reduction in both phenanthrene and pyrene biodegradation (89 and 88.2%, respectively). In control autoclaved soil, the rates of phenanthrene and pyrene removal were 14.2 and 28.7%, respectively, while in non-autoclaved soil, the rates were 68.7 and 53.2%, respectively. These results show that corn, which was previously shown to grow well in PAH-contaminated acidic soil, also can enhance PAH degradation in such soil. Inoculation with a known PAH degrader further enhanced PAH degradation in the presence of corn.

Shoot and root responses of Trifolium vesiculosum to boron fertilization in an acidic Brazilian soil

To analyze the influence of boron fertilization on shoot and root growth of Trifolium vesiculosum (arrowleaf clover), an acid soil profile (60 cm depth with 67 percent Al saturation) was recreated in a column (three layers of 20 cm each). Lime and fertilizer (P and K) were incorporated into the top 20 cm. The treatments consisted of six boron rates where boric acid was mixed throughout the profile. Addition of boron to soil with low pH and high Al increased the root and shoot growth, independent of the rate applied. Boron inhibited Al toxicity, but no effect was observed in the root length when Al was not present in the soil. It was also observed that there was more root growth below the plow layer (0-20 cm,) suggesting better root distribution in the soil profile which could be important for the plant growth, especially under drought conditions.

Estudos têm mostrado que o boro (B) afeta o crescimento das raízes em solo ácido reduzindo a toxidez do alumínio (Al). Para analisar a influência do boro no crescimento da parte aérea e raízes do Trifolium Vesiculosum (trevo vesiculoso) um perfil de solo ácido (60 cm de profundidade com 67 por cento de saturação de Al) foi recriado em uma coluna (três camadas com 20 cm cada). Calcário e adubos (P e K) foram incorporados na camada de 0-20 cm. Os tratamentos consistiram de seis doses de boro sendo o ácido bórico incorporado em todo o perfil. A adubação com boro em solo com baixo pH e elevado Al aumentou o crescimento da parte aérea e raízes, no entanto, independente da dose aplicada. Boro pode inibir a toxidez de Al, porém não observou-se efeito no comprimento de raízes sem a presença de Al no solo. Observou-se também um grande aumento no crescimento de raízes abaixo da camada arável (0-20 cm), fornecendo uma melhor distribuição de raízes no perfil do solo, o que pode ser importante para o crescimento da planta especialmente em condição de seca.