9.Harvesting and storage & Organic Agriculture

9. Harvesting and storage & Organic Agriculture

A couple of weeks before the bananas are ripe an (often blue) bag is put over the bananas. This is not So other animals won’t eat from them or anything no this is to extend the ripening process. Because they are not exposed to direct sunlight the ripening goes a lot slower. This is done so all banana bunches are ripe at the same time and they can be sold as one big harvest. Banana bunches are harvested with a curved knife when the fruits are fully developed, that is, 75% mature, the angles are becoming less prominent and the fruits on the upper hands are changing to light green; and the flower remnants (styles) are easily rubbed off the tips. Generally, this stage is reached 75 to 80 days after the opening of the first hand. Harvesting is always an two man job, one man cuts and the other one catches the bunch to makes sure they don’t hit the ground and get damaged.

The banana bunches are stored in warehouses or sheds. They provide cover from wind and rain but also from animals such as rodents. Before the bananas end up in the ware house they get sorted and cut into smaller bunches. They are packed in wooden or cardboard boxes with again a piece of plastic as an cover against the sun.

In the Dominican Republic are certified organic bananas grown by Banana Link. It is an non-profit organisation that doesn’t only grow organic bananas but also follows the labour standards that are set by the UN. They are mostly destined for the European market and then especially for the German market. Everything is as said done in an organic way. They us organic fertilizers non chemical pesticides and weed control is done by hand with machetes.

Bananas with protection bag

8. Weeds, plant disease and Insects

8. Weeds, plant disease and Insects

Pigweed is an very aggressive and herbicide resistant weed that is rapidly moving through all of Brazil. It is an weed that easily produces 200.000 seeds that can be carried away by the wind. This resistant pigweed is an result of the zero tillage system. Because you don’t open the soil or anything is it really hard to get rid of all the weeds, and throughout the years this weed survived and developed.

In other parts of Brazil is the temperature a big problem. Back in the days before the real global warming temperatures dropped during the off season and then the weeds would be killed because of the cold. But now the temperatures don’t drop that rapidly and so the weeds survive.

Recently a new disease developed and is spreading worldwide. A leaf spot  disease that we know as black Sigatoka disease is an disease that we can only find on banana plants. It causes premature ripening, reduces significant leaf area and causes 50% yield loss. It is harder to control and is more wide spread then the already common yellow Sigatoka disease. To get rid of this disease is an very labour intensive job that requires constant attention. You have to keep remove all affected leaves, keep spraying the herbicides regularly and an adequate spacing between plants so that the disease can’t jump from one to the next. 

Leave affected by black Sigatoka

7. Cropping system, Tillage and crop establishment

7. Cropping systems, Tillage and crop establishment

In the tropics of Brazil is Zero tillage or No-till farming very popular. Zero tillage means that you grow year after year without disturbing the soil through tillage. This zero tillage is very good for the soil. It increases the amount of water that infiltrates in the soil, it increases organic matter retention and cycling of nutrients and it increases the bio-diversity of the soil. And maybe the most important reason for the Brazilian farmers to do this is that it reduces soil erosion. The zero tillage works very well for the banana farms because they don’t use crop rotation. Crop rotation means that you switch your crop from one field to another to make sure you extract the maximum amount of nutrients out of the soil. Disadvantages are that the soil erosion is quite high because the soil gets not enough time to recover.

In the banana industry in Brazil is everything done manually. From planting and harvesting to spraying pests. This makes it an very labour intensive business. But it is not shocking that so much is done by hand because it is very hard to use big equipment on an banana farm. Because of the density is I not possible to use big machinery without damaging the crop. 

6. Soils

6. Soils

The main soil in Brazil is called by the FAO the Ferralsol. Ferralsol is the extremely weathered red or yellow soil that can be found in the humid tropics. It consists mostly out of the dominant clay mineral kaolinite and is also high in iron and aluminium oxides. The banana plant will grow and fruit under very poor conditions but will not flourish and be economically productive without deep, well-drained soil loam, rocky sand, marl, red laterite, volcanic ash, sandy clay, even heavy clay but not fine sand which holds water.

Besides the polluted soils and groundwater in Brazil due to excessive pesticide use is the fact that they extract a lot of nutrients and don’t replace them a big cause of the soil erosion in Brazil. The cause of this is the lack of knowledge with the farmers. They don’t now the plant biology so they don’t know what their plant needs want it extracts from the soil and what that does to their soil.

The graph below shows what the micronutrient up take is of the banana. So to maintain These levels an fertilizer that is high in potassium is required.

Banana plant nutrient uptake

5.Enviroment and Agroecosystems

Blog 5 Environment and Agroecosystems.

Brazil is an big tropical country that lies in the equatorial zone. This means that the temperatures are high (on average temperature of 26 Celsius degrees) as well as the humidity and that there is plenty of rain. Most rainfall falls during the winter and spring with 130 mm of rain per month. These conditions are ideal if you want to grow bananas.

Most farmers count on rainfall as their irrigation method. And the big problem they have is that they don’t conserve their water. This means that they have an shortage during the drought periods.   

Another problem the banana farmers face is that their banana plantations are located on hillsides or sloping pieces of land. A big negative effect of this is that it is conductive to soil erosion. So to tackle both problems they came up with drains. Drains are gutters that are dug by the farmers. They form an linked system that catch the fallen rain and transport it safely away from the field into an water facility. Often an pond or lake dug by the farmers. By redirecting the water through the drains they make sure no important soil is flooded. The water that is stored can be used again during periods of drought.   

 

 Example of a drain

Although the Brazilian farmers benefit a lot from the rainfall is it also their biggest downfall. Sometimes is the rainfall to much to handle and then the fields are simply flooded. The crops ‘drown’ and the harvest is destroyed.

Banana field destroyed by rain

Bananas are cultivated as an monocultural crop. They need lots of attention and provide a lot of shading what makes it hard for other plants to grow on the same field. But to improve carbon sequestration I would try to cover the ground with another small crop that can easily grow between the banana trunks this is called cover cropping. Cover cropping is the use of crops such as clover and small grains for protection and soil improvement between periods of regular crop production. Cover crops improve carbon sequestration by enhancing soil structure, and adding organic matter to the soil.

Conventional banana production in Brazil is not sustainable. It depends on frequent and heavy use of pesticides to reduce pests, increase yields, and to come close to the quality standards of importing countries. This has resulted in the contamination of soil, water, and the bananas. The Brazilian government should invest more in teaching the farmers how to grow bananas in an more sustainable and healthy way. The impact and pressure would grow if we make the consumers in the EU and US aware of it.

4. Improving Plants

Blog 4 Improving plants

Transgenic plants are plants that have been artificially inserted instead of getting them through pollination. This makes it possible to create new species that have an natural resistant against an bacteria or pest. Plants that are artificially inserted are often called Genetic modified crops or GM crops for short.

The now widely cultivated ‘Cavendish’ banana is also an GM banana. This banana entered the market after the then most cultivated banana the Gros Michel was wiped-out by the Panama disease. This was an fungus known as fusarium wilt. This showed us that we need banana species that are genetically modified  but still today the banana industry lacks good crossed banana species. And the now cultivated Cavendish banana is also threatened by an new disease.

Luckily recently Brazilian scientists came with an new banana specie. Brazilian scientists from the Empresa de Pesquisa Agropecuária e Extensão Rural de Santa Catarina (Epagri) and Brazilian Agricultural Research Corporation (Embrapa) have launched a new banana, the Belluna, which is, they say, more resistant to destructive banana diseases than other commercial varieties. The scientists have registered the Belluna with the Ministry of Agriculture, paving the way for the banana to be sold commercially. “We have three diseases that affect bananas in Brazil and in the world which are Yellow Sigatoka, Black Sigatoka and Panama disease,” said Edson Perito Amorin, the head of Embrapa’s breeding program. “Belluna is resistant to Yellow Sigatoka and Panama disease and moderately resistant to Black Sigatoka. In terms of resistance, it has a clear advantage over the varieties that are on the market today.” The variety, said Embrapa, can be grown organically, without the use of pesticides, due to its resistance. (Maura Maxwell, 2016)

3.Banana tree growth

3 plant physiology and growth

The banana tree is an perennial tree. This means that it grows for more than two years.  It takes the plant 9 to 12 months before the first flowers appear. The fruits then appear 90 days after the first flower. After fruiting, the pseudo stem dies, but offshoots will normally have developed from the base, so that the plant as a whole is perennial.  

All most all plants in the world are C3 plants and so is the banana. C3 plants are those which fix and reduce inorganic CO2 into organic compounds using only the C3 pathway in photosynthesis while C4 and CAM plants employ both C3 and C4 cycles. In other words, the first classification refers to those plants having C3 photosynthesis, C4 plants employ the C4 photosynthesis, and CAM plants the CAM photosynthesis.

Recent research had pointed out that Photoperiod certainly does affect the banana plant. Photoperiod is the time between sunset and sundown. A longer photoperiod during the  reproductive stage correlate with an increase rate of bunch appearance at the top 8 till 10 weeks later. And an long photoperiod during the mid-vegetative stage hastens the flowering of the plant.

Legume plants such as bananas can’t fixate atmospheric nitrogen. They can fixate nitrogen via the Rhizobacteria. That is an bacteria that nestles on the roots and helps in the process of converting useless N2 into NH3.