Advances and Trends in Agricultural Sciences Vol. 3

In order to select camu-camu superior genotypes, a comparative of clones from natural populations, farmer plantations and an experimental field of the National Institute of Agrarian Innovation (INIA), was established in 2004 in varzea, at the Peruvian Amazon Research Institute (IIAP). Nine harvests between 2006 and 2016 have been evaluated, including variables in vegetative and reproductive development states. Statistical analysis was performed using the SPSS program for analysis of variance and SELEGEN REML/BLUP for repetitivity analysis of “fruit yield” (FY) and “fruit weight” (FW) with 5 and 4 measurements (years) respectively. For FY, a repetitivity index r = 0.117±0.07 was obtained with a selective precision of 0.63 and efficiency of 1.84 where clones 69, 48, 58, 50, 61, 13, 18, 29, 49 and 32, were selected in descending order of merit. For FW, r = 0.690±0.294 was obtained with selective precision of 0.948, efficiency of 1.14 and selection of clones 44, 13, 26, 23, 69, 64 22, 52, 27 and 8. As for the content in ascorbic acid, clones 48, 32 and 35 occupied the first places with more than 2000 mg of ascorbic acid/100 g. The selections achieved strengthened the pre-improvement work by conferring vigoury fiavility of a long term research.

Banana is one of the most ancient crops in the world. It is the most appreciated fruit because of its multipurpose use as food. Being perishable, it deteriorates very quickly. Post-harvest treatment with various suitable chemicals like potassium permanganate, ethrel, dipping in hot water, cold water and use of polythene bags can be used for enhancing shelf-life. Post-harvest treatment of banana fingers with different concentrations of potassium permanganate, ethrel and dippings in hot and cold water and analysis of shelf-life of treated fruits through titratable acidity, ascorbic acid and TSS content of fruit has been carried out during storage. The analysis revealed superiority of ethrel 600 ppm and potassium permanganate as ethylene inhibitor and absorbent to improve storage life banana fruits without loss of nutrient content.

Crop loss due to pest attack occurs regardless of the fact that a large quantity of pesticides is used annually. Use of chemical pesticides not only destroy the beneficial enemies but also alter the physiology of crop making more susceptible to pest attack. This chapter focuses on the scope and strategies of crop protection using bio-organic amendments with special reference to infestation of major pests, foliar disease and leaf productivity of mulberry. Massive utilization of inorganic fertilizers for a prolonged period leads to alteration of the soil chemical properties, the availability and uptake of nutrients by the plants. Several studies found that under water stress conditions, crops in organic agriculture systems produce significantly higher yields than comparable with other conventional crops using inorganic package and practices. Researchers have established that increase nitrogen levels in the tissues of the plants may decrease resistance and increase susceptibility to pest attacks. Although clarity is needed to establish the relationship between crop nutrition and pests, most studies have shown that insect pests like aphids and mites are more prone to nitrogen fertilizers. With relevant to above fact adoption of organic package and practices is needed for sustainable yield of crops as well as to provide exact nutrient requirements to the crop those prone to pest attack.

A field study was conducted at Atonsu, Sekyere Central District, Ghana from 2013 to 2014, to (i) determine the effects of Moringa oleifera, Chromolaena odorata and Panicum maximum as ex-situ mulches, on soil nematodes population after two years of yam cropping and (ii) assess the effects of the soil nematodes on the yield and physical tuber quality of yam. The field experiment was a 3x3 factorial arrangement in a randomized complete block design with three replications. The first factor was ex-situ mulch types at three levels; Panicum maximum (farmers’ choice), Chromolaena odorata and Moringa oleifera. The second factor was natural fallow aged systems at three levels: 3, 5 and 7 years old. Data collected included nematode population changes, total tuber yield of yam and tuber physical quality assessment. Generally, Meloidogyne spp., Pratylenchus spp. and Scutellonema spp. were the nematode genera identified. However, Scutellonema spp. was found to be the most pathogenic nematode affecting yam tuber yield and physical quality. Chromolaena and Moringa mulches suppressed Scutellonema spp. populations by 80.7% and 76.2% respectively as compared to the Panicum maximum mulch. The suppressed Scutellonema spp. population significantly contributed to higher tuber yields and good tuber physical quality under the M. oleifera and C. odorata mulches in comparison to the P. maximum mulch.

Aim: The aim of this work was to explore the nutrients, minerals, beta-carotene and total carotenoid contents of five sweet potato varieties viz., Agric orange flesh, Agric white, Red skin, Orange flesh and T.U. purple and present the findings in a language that the average reader can understand. This will help consumers to appreciate what they are feeding their bodies with when they eat the different varieties of sweet potato.

Study Design: The sweet potato vines at six week stage were cut into 1.2 m each and transplanted in parallel lines on the same 1.2 m x 2.6 m bed, spaced about 0.52 m from each other in Dukumah Garden. There were five such beds and vine cuttings transplanted in the same order on each bed. The essence was to provide the same soil and environment so that at harvest, the content of their nutrients, mineral salts and other food factors can be compared.

Study Site: The study, which took four months, was conducted in the Dukumah Garden in Bolgatanga Municipality (10.7875°N, 0.8580°W) of the Upper East Region of Ghana.

Methodology: The sweet potatoes were harvested four months after transplanting on the same day. Samples of the various varieties were collected, parceled, appropriately labelled and hand-delivered to the Food Chemistry Laboratory of Kwame Nkrumah University of Science and Technology for proximate analysis (%), total carotenoids and beta-carotene concentrations in milligrammes per gram (mg/g) and concentrations of the minerals, namely magnesium (Mg), sodium (Na), potassium (K), calcium (Ca), iron (Fe) and zinc (Zn) in milligrammes per kilogramme (mg/kg).

Results: All the five varieties of sweet potato were found to be nutritious. Protein content ranged from 3.82% in the Agric white variety to 0.11% in Agric orange flesh. Fat content ranged from 4.84% in orange flesh variety to 1.74% in red skin. Crude fibre content was between 1.77% in Agric orange flesh and 0.10% in T.U. purple. Total carbohydrate varied from 23.2% in Agric orange flesh variety to 15.8% in Agric white one. Moisture was high in all the varieties, ranging from 75.78% in Agric white variety to 71.04% in Orange flesh one. The Orange flesh variety had the highest ash content of 1.56%. All the varieties contained high concentrations of Mg but low concentrations of Na and K. The highest concentration of Ca (8250.70±0.06 mg/kg) was recorded in T.U. purple. The concentrations of Fe in the sweet potato varieties decreased in the following order: T.U. purple>Red skin>Orange flesh>Agric orange flesh>Agric white. The highest (123.12±0.00 mg/kg) and the lowest (33.10±0.00 mg/kg) Zn concentration were recorded in the orange flesh and Agric white varieties, respectively. The concentration of beta-carotene (mg/kg) in five sweet potato varieties was in the following order: Agric orange flesh<<Agric white<Red skin<Orange flesh<T.U. purple.

Conclusion: The five varieties of sweet potato were found to be rich in proteins, total carbohydrates and fats. They were observed to vary in macro- and micronutrients, beta-carotene and total carotenoids contents. T.U. purple variety was identified to be the richest source of Ca and beta-carotene. Thus, the sweet potato varieties may be of considerable importance in ameliorating nutrient, mineral as well as beta-carotene malnutrition in poorly resourced areas of the developing countries.

Saline groundwater occurs in the Karha River basin area. Groundwater is one of the major resource for the peoples of River area for domestic and agricultural purpose. The groundwater samples from study area were collected in the period of post-monsoon (POM) and pre-monsoon (PRM) seasons. The various physico-chemical parameters such as pH, Electrical conductivity, Ca²⁺, Mg²⁺, Na⁺, K⁺, total dissolved solids (TDS), total hardness (TH), HCO₃^-, Cl^-, and SO₄^2- were determined using standard procedures of APHA.  The results of analysis were compared with the drinking water quality standards of Indian Standard Institute (BIS) and World Health Organization (WHO). For suitability of groundwater for agricultural purposes, groundwater data was compared with standard parameter of FAO. The average annual values of the electrical conductivity of groundwater ranged from 504 to 8624 μS/cm in the study period. In Karha River basin area the salinity of groundwater was considerable. 24% samples were EC up to 750 μS/cm which is low salinity and suitable for all purposes such as drinking, domestic and agricultural.  In rest of the area 76% groundwater samples showed high to very salinity (EC > 2250 μS/cm). Higher saline water is not suitable for drinking, domestic and agricultural purpose. The soluble sodium percentage values ranged from 7.68 to 92.83%. 18% groundwater samples from the study area showed higher soluble sodium percentage (>60%), indicating, groundwater in the study area was doubtful to unsuitable for irrigation purpose.

Aims: This study characterized biochemical compound variability that influence green bean quality in C. canephora as a basis for identifying heterogeneous genotypes for use in crop improvement because genetic erosion aided by climate change effects is gradually threatening the cultivation of Ugandan Robusta coffee (Coffea canephora) local races.

Study Design: Four hundred and fifty four accessions from twenty four districts were analyzed with Near Infra Red Spectroscopy (NIRS) for six biochemical compounds using calibrations developed at CIRAD, France.

Place and Duration of Study: This work was conducted at the National Coffee Resources Research Institute (NaCORRI), Uganda between January 2007 and December 2013.

Methodology: Spectrometer Nirsystem 6500 Foss- (Denmark) machine and Software ISI NIRS 2 version 4.11 (Infra Soft International, Port Matilda, USA) were used to analyze ground samples in diffuse reflectance from 400 nm to 2500 nm (2 nm steps) and predictive models were used to quantify the biochemical contents in the green beans. Data was analyzed with XLSTAT version 2011.2.05 (Addinsoft), Paris, France.

Results: Chlorogenic acid and fat concentrations of 13.26 and 13.19% dry matter respectively reported in this study were much higher than 5.88 and 9.0% dry matter respectively reported earlier. Caffeine concentrations were positively significantly correlated with cholorogenic acid but negatively significantly correlated with trigonelline, sucrose, fat and dry matter contents. Caffeine and chlorogenic acid concentrations increased with age whereas trigonelline declined as trees aged. Chlorogenic acid and trigonelline concentrations were at their lowest levels in elevations of between 1000- 1200 metres above sea level and like fat and dry matter concentrations, the compounds were at their highest levels in higher elevations of about 1500 metres above sea level. Local landraces, ‘’nganda’’ and ‘’erecta’’ had higher concentrations of chlorogenic acid, sucrose and caffeine than improved, hybrid and commercial types.

Conclusions: Ugandan C. canephora caffeine content was lower than that of West-African Robusta coffee but higher than that of Arabica coffee. Four distinct diversity groups derived from the six biochemical compounds represented the major organoleptic categories. The results reported here will be useful in defining the desirable cup qualities of Robusta coffee as demanded by world markets.

Aims: Evaluate whether mechanical damage and storage conditions affect the quality of the ‘Markies’ potato for processing.

Study Design: The experimental design was the completely randomized, in the scheme of splitplots. The plots were composed of treatments with and without mechanical damage and the subplots were made up by the evaluation times, with 5 replicates, where the experimental unit was composed of 2 tubers.

Place and Duration of Study: Tubers of the ‘Markies’ cultivar from the producing region of Perdizes, State of Minas Gerais, were planted in June 2016 and harvested in October 2016.

Methodology: The tubers were stored for 2 months at 8°C and further divided into treatment with damage, in which the tubers were subjected to impact and abrasion and control treatment, in which the tubers were not damaged. After that, they were stored at 28°C and evaluated for their loss of loss of accumulated fresh mass (FML), total soluble sugar (TSS), reducing sugar (RS), nonreducing sugar (NRS) and color after frying in the periods of 0, 12, 24, 36 and 48 h after being placed at room temperature.

Results: The mechanical damage in the tubers increased FML, however, it did not affect the content of TSS, NRS, RS and color after frying. Increases were observed in the content of TSS and NRS after 12 h of evaluation. Grade 2 was assigned to the coloring scale after frying for the tubers regardless of treatment or evaluation period.

Conclusion: Mechanical damage increases the FML and the ‘Markies’ cultivar is suitable for the industry of pre-fried potato processing even under the occurrence of mechanical damage and exposure to high temperatures.

Plant assemblage organization along physical environmental gradients remains a central issue of community on local, regional or continental scales. Mount Oku, commonly known as KilumIjim, situated at the North-west Cameroon has the most important remnant of Afromontane forest in Central Africa. These forests are recognized as a globally important center of endemism and a hotspot for biodiversity conservation but they are now undergoing unprecedented degradation. The aim of this study is to identify different plant assemblages in Mount Oku forests. In order to explore variations in vegetation composition of the study area, we realized 102 floristic plots along an altitudinal gradient. The floristic plots were subjected to a hierarchical cluster analysis (HC) using the Ward method. Our results allowed us to reveal 9 plant assemblages on Mount Oku, situated at different altitudinal levels. At the landscape level, this forest cover is old, but the plant communities composing it are largely recent because they emerge from secondary dynamics following various disturbances of the inner forest (Crops, pastures, logging, etc.). These plant communities cover a large altitudinal range. However there are still communities of ancient forests but very disturbed, situated on altitudinal levels from about 1900 to 2600 m. The general composition of the forest flora of Mount Oku indicates that this vegetation has preserved characteristics of a tropical Afromontane flora. The results show that the composition of plant communities is determined mainly by human activities that tend to erase the influence of natural factors such as altitude.

There were factors affecting erosion such as climate, soil type, vegetation and topography. Upland areas were denuding exponentially due to the fact that those people looking for livelihood had little concern and awareness on environmental sustainability and management. Upland farming practices that was easy like weeding, pest control and fertilization were often carried out without soil erosion control and water management. The result of the study revealed that an area with intercropped permanent crops has less amount of soil eroded or tolerable annual soil loss. But the areas with short duration crops (cash crops) and which adopted the same cropping pattern from the previous season resulted to severe soil erosion. Calculated annual soil erosion were 3.33, 4.57, 23.18, 0.31 tons and zero erosion for Site 1, Site 2, Site 3, Site 4, and Site 5, respectively.

Plant genetic resources are the biological basis of global food security. Agricultural diversity and genetic resources should be used more effectively to sustain the current level of food production and to solve future problems. The importance of plant genetic resources in the improvement of varieties with new features is indisputably known. The most effective use of plant genetic resources is undoubtedly in plant breeding and improvement of new varieties. In other words, it is used as a genitor. Since the cultivars are often inadequate in many genes, especially biotic and abiotic stress factors (diseases, pests, cold, drought, etc.) breeders constantly search for new sources of genetic materials. This review is based on reports in the landraces (primitive) varieties and crop wild relatives to explain the importance of genetic resources in plant breeding of reviewing scientific literature to pass.

Abundant mulberry genotypes are accessible in nature, they are deficient in one or the other important economic trait required for silkworm Bombyx mori L. as mulberry leaf is the sole food. In the present experiment, as S₅₄ mulberry genotype leaves are very much suited for rearing young age (Chawki) silkworms, an effort has been made to induce phytomorphological variability in S₅₄ mulberry genotype using gamma rays. RBD Method with three replications / treatment was followed. Experiment was performed in Mulberry garden, Department of Sericulture, Jnana Bharathi Campus, Bangalore University and Mist chamber, Indian Institute of Horticultural Research (IIHR), Bangalore, Karnataka, India. Gamma ray (1kR-10Kr) was used to induce variability in juvenile twigs of mulberry for various agro-botanical characters viz., sprouting, rooting, internodal distance, leaf area, plant height etc. and leaves were exposed to biochemical analysis. Mulberry genotype S₅₄ showed linear decrease in growth parameters with the increased gamma ray dosage and plants exhibited variability with increased rooting (81.33%), plant height (147.86 cm) and leaf area (146.22 cm²) when compared to control in M₁ generation at 7kR. Mutants displaying encouraging characters were grown for M₂ generation which exhibited marked enhancement in growth and yield parameters. Biochemical constituents in S₅₄ mutant leaves recorded at 7kR revealed increased proteins, carbohydrate, chlorophyll a and b. Mulberry cuttings irradiated with gamma ray (7kR) exhibited favorable characters in rooting, plant height and leaf area over the control in M₁ generation and mutants were grown for M₂ generation and marked improvement in growth, yield and bio-chemical parameters were witnessed.

Studies of dumpsites have revealed that the surrounding soils and water are contaminated with high threshold of heavy metals through anthropogenic inputs. In this review, the uptake and toxicity risks of these heavy metals by habitual edible plants at levels above threshold limit and the implications for public health have been discussed. Edible plants are plants with nutritional and medicinal potentials which can salvage numerous human and animal needs when taken. Edible plants like most other underutilized plants in dumpsites have developed mechanisms which enable them to not only survive but accumulate high level of toxic heavy metals due to high level of environmental metal load in the dumpsites. This ultimately could lead to high human and animal exposure to these toxic elements through food-chain/food-web or direct ingestion of soils. The toxic effects caused by excess concentrations of these heavy metals in living organisms vary considerably and present numerous clinical situations ranging from neurological disorder, cellular damage among others and death in extreme cases. This review suggest the urgent need for policy makers to regulate the use of dumpsites for arable farming and the dependence on edible plants in dumpsites to avert heavy metal poisoning in populations.