Advances and Trends in Agricultural Sciences Vol. 1

This study was carried out to develop transformation protocol for the possible improvement of local cultivars of tomatoes in Nigeria using complete randomized design (CRD). The research was conducted at the Plant Biotechnology Centre, International Institute of Tropical Agriculture (IITA), Ibadan, Oyo State, Nigeria between May 2009 and December 2009. Seeds of three promising farmer preferred varieties of cultivars of tomatoes namely Ibadan local, Ife and JM94/46 were selected and cultivated in-vitro. Sterile cotyledon and leaf explants were transformed using Agrobacterium tumefaciens strain LBA4404 with plasmid (pOYE153). Transformed plants were analyzed using GUS assay and PCR methods. Results showed that leaf explants had higher transformation efficiency than cotyledon explants in the three cultivars. Ife cultivar had the best transformation efficiency in both explant types - leaf 42.5% and cotyledon 8.89%. Histochemical GUS assay of transgenic plants showed blue coloration in leaves, stems and roots. PCR analysis showed amplification of 600 bp fragments of GUS and nptII genes in the transgenic plants on 1.0% agarose gel. The GUS and nptII genes were successfully integrated into the three cultivars of tomatoes thereby providing a reliable transformation protocol for the genetic improvement of local cultivars of tomatoes for desirable traits such as longer shelf-life, pest and disease resistance, enhanced nutrients, higher soluble solids, etc. The GUS and nptII genes were successfully integrated into the three cultivars of tomatoes thereby providing a reliable transformation protocol for the genetic improvement of local cultivars of tomatoes for desirable traits such as longer shelf-life, pest and disease resistance, enhanced nutrients, higher soluble solids, etc.

We obtained honey from the blooming flowers of tea plants (Camellia sinensis L.) pollinated by honeybees (Apis mellifera L.). Functional amino acids, theanine, which is a unique ingredient to tea, was determined using reversed-phase chromatography. We also determined the main ingredients: caffeine and catechins. The obtained honey contained theanine, which shows that it was derived from tea flowers. The theanine concentration of the nectar of the tea flowers exceeded that of the honey. Caffeine was detected (but no catechins) in both the honey and the nectar of the tea flowers. Our results refute the previously held view that tea nectar is toxic to honeybees. Our new finding reveals that it is possible to obtain honey from the nectar of tea flowers. The obtained honey and the nectar of tea flowers contained a very rare amino acid, theanine, indicating that the honey was derived from tea flowers. Furthermore, the nectar of tea flower contained the best caffeine concentration that activated the brain function of honeybees to produce the honey.

Consequence upon the geometrically rising world population and the increasing pressure on food items, it has become increasingly necessary to increase food production from the present level. The possibility of achieving this is not only to increase production but also to protect the crops cultivated. Crop protection can be achieved through several means. One of such is the use of pesticides. This paper therefore reviews the use of neem extracts as bio-pesticides among other plant species with inherent pesticidal activities. It is no doubt that the chemical pesticides or insecticides possess inherent toxic substances that endangers the ecological environment, operators of application equipment, soil microbiota and consumers of the agricultural products. It is therefore important that we encourage the use of biological pesticides as they affect only target pest, are easily biodegradable, increase farm land fertility, environmentally friendly, cost effective and ease of availability. It is also important that because of the low cost of production of bio-pesticides it should be encouraged as an option in African countries especially Nigeria in agricultural practices. The practice of farmers making their own neem-based products for pest control would reduce their dependence on external inputs for agriculture. It would also reduce their cost of pest control to almost zero, leaving only labour as a potential expenditure item. Pests can also be controlled without the use of toxic chemical pesticides, which will reduce the harm posed to humans and the environment alike. There is wide scope for innovation in developing neem as an efficient bio-pesticide. There is enough information to encourage the use of different neem extracts. With the increasing trend of using bio fertilizers, insecticides and pesticides, neem should be increasingly cultivated and grown all over the world to get active ingredient-azadirachtin, responsible for stopping the growth cycle of pests. Neem is also assuming a lot of importance in crop management. Considering the fact that neem is not only a cheaper, naturally occurring product and an effective method to control pests and insects, but also has no side effects on plants or other living beings especially soil micro biota.

Bananas are grown in the world mainly for their economic and nutritional value. High perishable nature of banana leads to quality deterioration which distracts consumer and hence high postharvest losses in the market. Climacteric nature of banana make these postharvest losses accelerate by triggering ethylene induced ripening process. Extending banana shelf life could be a considerable commercial benefit for both exporters and retailers. Treatments such as fungicides, heat treatments and low temperature storage are being applied for extending the shelf life of banana. However, nowadays, increased public concern over presence of chemical residues has progressively leads the adoption of heat treatment methods which substitutes as a non-damaging physical treatment for chemical prevention. Heat treatment is one of effective postharvest techniques which have been using as a plant quarantine procedure in other fruits. Indeed, the overall quality of fresh produce treated with optimal hot water temperatures is significantly better than untreated produce, as determined by a sharp reduction in decay incidence and maintenance of several quality traits. Heat treatment can be applied as vapor heat, hot water immersion (hot water dip) of the fruit until the core temperature reaches required effective temperature depending on cultivar. Banana fruit ripening effectively can be delayed by application of hot water treatments such as 40°C for five minutes. These treatments are not negatively effect on fruit taste, brix value around 40°C treatments. Further, more positively suppressed the microbial growth on fruit surface which supportive to the extend shelf life of banana. All findings related to heat treatments on banana suggest that hot water treatment, 40-50°C depending on cultivar, is most suitable for delaying de-greening and hence delaying the ripening during storage at ambient temperature. Food taste and soluble solid content not affected badly by hot water treatments especially up to 40ºC. Microbial growth effectively controlled by hot water treatment over 40°C. As with all this it can be concluded that heat treatments led to increase postharvest life without affecting the food quality of banana.

Caffeine is one of the main components of green tea and has side effects such as sleeplessness. Senior citizens, children, and pregnant woman should avoid tea despite its known beneficial effects. In this study, we developed green tea with reduced caffeine content (low caffeine tea) as a palatable tea that can be offered to everyone. To reduce the tea’s caffeine content, we subjected the plucked tea leaves to a hot-water spray process, and successfully produced a low caffeine tea infusion with 30% the caffeine content. The concentrations of other main components, such as catechins and theanine, in the low caffeine tea infusion did not differ from the control. Further, the physiological function of the tea was assessed; the anti-oxidative activity was investigated using a stable free radical and the anti-lipase activity using an artificial substrate. There were no significant differences between the infusions of low caffeine tea and green tea in anti-oxidative and anti-lipase activities. The results showed that our developed low caffeine tea could be an attractive high quality tea with health benefits for everyone.

The Hausa potato (Solenostemon rotundifolius (Poir)) J. K. Morton is a tropical, multipurpose crop with different economic values. Its productivity is, however, low in terms of fresh tuber yield in the accessions available for cultivation in Nigeria. Consequently, many farmers are not encouraged to cultivate the crop, thereby limiting its popularity. This study was, therefore, designed to screen different accessions of the Hausa potato for productivity in the Jos-Plateau environment, Nigeria. The nine accessions (Manchok 1, Manchok 2, Bokkos 1, Bokkos 2, Bikka-Baban, Mujir, NRCRI, (White), Tukwak and Langtang) were laid out in a randomized complete block design with five (5) replications. Results indicate that percentage emergence, number of branches per plant, leaf area index (LAI), days to flowering, number of flowers per plant, relative growth rate, net assimilation rate, tuber length, tuber girth, root-top ratio, stand count at harvest, mean tuber weight, dry matter content and fresh tuber yield varied with accessions. Positive correlations were observed between the number of branches and number of flowers and mean tuber weight, root-top ratio and tuber yield, relative growth rate and net assimilation rate, tuber length and harvest index, relative growth rate and harvest index, tuber length and mean tuber weight as well as harvest index. The relative growth rate and net assimilation rate were also positively correlated. Moisture content was negatively correlated with nitrogen free extract. Protein was positively correlated with NFE (0.553*), but negatively correlated with calcium (-0.855**). Ash content and iron were negatively correlated (-0.655*). Total tuber yield was generally low in all the accessions. The positive associations among some growth and yield attributes suggests that these attributes could be used as selection indices in the improvement of the Hausa potato. The crop has the potential to address vitamin C deficiency in children. There is, therefore, the need to intensify research and popularize the production and consumption of the crop. The study also suggests investigation into the source-sink relationship in the Hausa potato.

The beneficial effects of green tea are well documented. However, most research has reported the effects of green tea brewed solely from leaves or leaf extracts. We focused on tea roots and developed a hydroponic system to explore the effect on roots that biosynthesize one of the rarest functional amino acids, theanine. The level of theanine in tea roots was much higher than in leaves, which was analyzed using HPLC. Moreover, a higher level of theanine was detected in white rootlets than in lignified roots. Thus, tea roots cultured hydroponically in a controlled environment might be considered a natural drug containing theanine, which could lead to synergistic effects with other ingredients of the root. This novel medicinal material from the roots demonstrates a significant medical function for tea that extends beyond its leaves.

Background: Sugarcane is a major commercial crop grown in tropical and subtropical areas of the world, including West and Central Africa. Across this region, smut, leaf scald and pokkah boeng are considered as endemic diseases, the first two being economically important.

Aims: The overall objective of study was to contribute to sugarcane yield improvement in Ivory Coast. The specific objective was to evaluate the diversity of susceptible sugarcane genotypes mainly in first ratoon crop to three major endemic diseases under natural infection, namely leaf scald, smut and pokkah boeng.

Methodology: The study was carried out over 2 seasons (2016-18) as plant and first ratoon cane at Ferké 1 experimental station under full covering sprinkler irrigation in northern Ivory Coast. Treatments were composed of 863 sugarcane genotypes split into 39 families planted at single row density. Planting was done per genotype in rows of 3 m long depending on families, without replication and compared to the check variety SP70/1006. That check was replicated every five rows to ease comparison with the clones. Phytosanitary observations regarding the three endemic diseases made at the age of five months were subjected to a series of multivariate analyses.

Results: The study showed that most relevant diseases determining the diversity of susceptible sugarcane genotypes were, in descending order, pokkah boeng, smut and leaf scald. Increase in clone infestations on first ratoon cane compared with plant cane was observed regarding the three endemic diseases but more importantly for smut by 51%. The dendrogram deduced from cluster analysis showed that infected genotypes were split into six groups with same families belonging often to different clusters so that no family investigated specifically susceptible or resistant to any disease was determined. In other words, each family investigated was composed of disease-free as well as susceptible genotypes in proportions varying from one family to another.

Conclusions: All families investigated were relevant to maintain the diversity required for the breeding process under way. Examples of recommended families were the following: disease-free (F02, F03, F04, F05, F06); resistant (F01, F06, F07, F08, F09); moderately resistant (F10, F11, F12, F13, F14). It came out from the study that most relevant diseases determining the diversity of susceptible sugarcane genotypes were, in descending order, pokkah boeng, smut and leaf scald. Increase in clone infestations on first ratoon cane compared with plant cane was observed regarding the three endemic diseases but more importantly for smut by 51%. Each family investigated was composed of disease-free as well as susceptible genotypes in a certain proportion which varied from one family to another. Cluster 5 was the most prolific of infected genotypes with 286 clones (33%) split into 36 families (92%) whereas clusters 2, 3 and 4 were the least prolific ones, with 42, 52 and 56 infected genotypes split into 14, 23 and 21 families, respectively. Clusters 1 and 2 were much more associated with genotypes susceptible to smut and pokkah boeng but also with genotypes moderately susceptible to pokkah boeng. Clusters 3 and 4 were associated with genotypes susceptible or highly susceptible to leaf scald. In contrast, clusters 0, 5 and 6 were related to disease-free, resistant or moderately resistant genotypes and which crosses or families would, therefore, be recommended for Ferké agro-ecology. Examples of such families were the following: disease-free (F02, F03, F04, F05, F06); resistant (F01, F06, F07, F08, F09); moderately resistant (F10, F11, F12, F13, F14).

The use of riparian areas as water quality management tools, primarily derived from the studies of agricultural watersheds, where low phosphorus and large nitrate reductions in the suspended sediment are observed. A riparian strip performs many key functions, such as nutrient uptake, trapping of sediment or pesticides. Therefore, a number of different forms of protection strips have been applied in the field according to relief, steepness and location for use. Studies assessing technologies to design riparian strips using plant covers, based on sediment yield in river basins, are required for environmental protection. The removal of semi-shrubby, native vegetation in the Brazilian semiarid region, has contributed to the degradation of semiarid basins. The aim of this study was to design a riparian strip for the Jacu River in the semiarid region of Pernambuco as a function of sediment yield. Experiments were conducted during the years 2008-2011 in the Jacu River basin at Serra Talhada, Pernambuco State, Brazil. The sediment yield in the Jacu River channel was obtained by measuring suspended and background solid discharge. The riparian strip width estimated in the riparian areas of the Jacu River basin was 15 m. It was concluded that for this study, the sediment yield time and observation of hydrological data were important factors for determining the riparian strip width with greater security.

 The abiotic stresses are the main factors associated to low productivity, since they are related to the soil and the conditions of the environmental adversities. These are difficult to control factors and when severely affects production dramatically. The expand agricultural production to new crop areas in the tropical regions is an important strategy to supply the huge demand for food and renewable energy sources. However toxic aluminum (Al) present in tropical soils is a limiting factor for agricultural production. The objective of this study was to identify Al-tolerant and Al-sensitive sugarcane genotypes, based on phenotypic plasticity. Eleven sugarcane genotypes were evaluated under non-stress and Al-stress conditions. Genetic variability regarding Al tolerance was observed among the sugarcane genotypes by phenotypic plasticity. Al-stress caused a reduction in the primary root length and in the shoot dry weight, but an increase in the lateral root length. There was a difference between the genotypes related to Al accumulation in the roots and shoot, suggesting the existence of distinct tolerance mechanisms. Based on phenotypic plasticity genotypes can be classified as tolerant or sensitive to Al. The phenotypic plasticity is a simple form of analysis; however, it has great information about the behavior of the genotype. We characterized genotypes associated with Al-stress. The characterization of contrasting genotypes will be important for breeding programs involving sugarcane yield in regions subjected to stress.

To improve the production of zucchini in Côte d'Ivoire and particularly in to Korhogo Department, a study was carried out at the Peleforo Gon Coulibaly University research site and at four farmers’ sites during dry and rainy seasons. On each plot, the number of healthy and attacked fruits was evaluated, based on a random sample of 100 fruits. The attacked fruits were transported to the laboratory and incubated to determine the causative agents. The methods and pesticides used to control insect pests by farmers were listed. During the rainy season, 86.06% of the fruit was attacked by flies while 13.94% remained healthy. In the dry season, for a total of 9,617 controlled fruits, 7,439 (77.35%) were healthy and 22.65% were attacked. Four insects species emerged from infested fruit. They were Bactrocera cucurbitae, Dacus ciliatus, Dacus bivittatus, belonging to the family of Tephritidae, and Scaeva pyrastri belonging to Syrphidae. The method used by farmers to control pests was not effective. In conclusion, flies represent the limiting factor of zucchini production during the rainy season in to Korhogo Department. At the end of this research, it emerges that the main zucchini pests in the Korhogo Department are Bactrocera cucurbitae, Dacus ciliatus, and Dacus bivittatus of the family Tephritidae. The species Scaeva pyrastri of the family of Syrphidae is not responsible for the loss of fruit; it comes only secondarily after the attack of Tephritidae. Pesticides used by growers in the control of pests are not indicated. Because of the strong presence of flies in the rainy season on zucchini and the damage they cause, the production of zucchini during this season may not be profitable.

Understanding of different levels of soil calcium (Ca), magnesium (Mg), potassium (K), sodium (Na), cation exchange capacity (CEC), and percentage base saturation (BS), is important in the management of forest ecosystems. However, there is limited documentation on the status of these elements in the undisturbed forest sites (CFS) crop-agriculture (ADS) and livestock grazing (DGS) disturbances in the tropical coastal forests. This chapter attempts to address this deficit by presenting soil fertility based on exchangeable bases’ status and variations across undisturbed forest sites (used as a control), crop-agriculture and livestock disturbed sites in the coastal zone of Tanzania. The chapter aims to add knowledge on the management of tropical coastal forests. Indeed, this chapter shows that crop-agriculture and livestock grazing disturb soil chemical properties in tropical coastal forests. Therefore, it is essential to protect undisturbed forest while putting more efforts to restore the disturbed sites for sustainable forest management along the coastal areas.

Food production and supply system contributed more than 90% of the nitrogen originated in south Asian megacities that pollute the surface water. Five megacities of three South Asian countries were considered in this study. These countries are developing and their population is increasing tremendously. All the five megacities are very densely urbanized. A numerical model has been used to calculate the anthropogenic nitrogen load on the environment. FAO statistics on fertilizer consumption and food balance data sheet has been used to calculate the nitrogen load. Human waste plays the vital role in nitrogen production of south Asian megacities. So, in these contexts the nitrogen load for all the study areas extremely harmful for environment and ever increasing population also increased the load of nitrogen on surface water produced from human waste which also very awful for the environment. So, a proper sewage treatment facility is compulsory for all the study areas.  Four findings has been identified are; (1) for all three countries, rice and wheat production-supply produce the maximum amount of nitrogen. (2) Though the amount of nitrogen due to fertilizer input more or less same among the countries but amount of produced nitrogen due to human waste is huge in Bangladesh. (3) Moreover, in city scale, the amount of nitrogen due to fertilizer input is maximum in Delhi city and negligible in Kolkata due to an insignificant amount of farmland. (4) Interestingly, the maximum amount of nitrogen load in surface water is in Kolkata city due to human waste but Mumbai and Dhaka shows a medium amount of nitrogen load. This can give the estimation for city wise untreated nitrate content and this is necessary for the capacity development of existing sewerage treatment plant as well as the establishment of new plants.

Aims: This study determined a nutritive solution and evaluated the performance in the development, production and quality of strawberry cultivated in the substrate.

Study Design: The treatments were commercial and recommended nutritional solutions for strawberry using the methods of Castelane and Araújo (C.A.), Furlani and Fernandes Junior (F.F.J.) and the proposed solution with seven replicates.

Place and Duration of Study: The experiment was carried out in the experimental area of the Federal Technological University of Paraná, Brazil, in the period between May and December 2014.

Methodology: Agronomic variables such as yield, number of fruits, nutrient content, physiological indicators, physical and chemical characteristics of fruits were analysed.

Results: The proposed nutrient solution resulted in larger masses of fresh and dry matter (225.4 g plant-1 and 27.5 g plant^-1), number of fruits (40.1) and fresh fruit mass (750.4 g plant-¹), in relation to the other evaluated solutions. The proposed solution resulted in better physical and chemical characteristics such as soluble solids, reducing and total sugars, anthocyanins, flavonoids, phenolic compounds and ascorbic acid and the strawberry fruits presented an attractive colour and met the quality standards for the consumer. The highest levels of nitrogen (33.7 g kg^-1), phosphorus (9.3 g kg-1), and potassium (28.2 g kg^-1) in the leaf tissue were found in the proposed solution and contributed to productivity and fruit quality gains of a strawberry.

Conclusion: These results provide a nutrient base and can be adapted to other cultivars in different locations. In this study, the proposed nutrient solution contributed to productivity gains, fruit quality and comes as an option of adequate nutrient content for the strawberry, with ionic balance, without excess nutrients. These results provide a nutrient base and can be adapted to other cultivars in different locations.