COTTON IN THE NATIONAL MARKET
Brazil is the fourth largest producer and second largest exporter of cotton fiber in the world.
What do you need to know
The cotton crop requires high levels of nutrients such as nitrogen (N), phosphorus (P) and potassium (K) to improve vigor and yield.
The cotton crop is very demanding in nitrogen (N). The total amounts of nitrogen extracted by the cotton plant to produce a ton of seed cotton, found in the literature, are in the range of 48 to 85 kg of N. The peak of nitrogen (N) uptake occurs between the first and second week of plant development, which corresponds to about 60 days of emergence, indicating that this is the limit for applying all the nitrogen in the cotton crop.
To obtain greater efficiency in the use of nitrogen fertilization, Cibra recommends Nitrocap, which is a fertilizer with a high concentration of nitrogen, ideal for providing lower losses by volatilization by increasing nitrogen (N) absorption. The efficiency of nitrogen fertilization results in greater plant productivity and vigor.
For the cotton plant to produce a ton of seed cotton, phosphorus is extracted in the range of 13 to 25 kg of P2O5. Phosphorus (P) is an important nutrient for increasing early root development and anticipation of capsule establishment and fiber maturity. Potassium (K) is absorbed in large amounts by the cotton plant and is important for increasing maturity, fiber length and reducing premature senescence.
To provide these nutrients, Cibra recommends the BaseFort fertilizer, which also provides sulfur in its formulation, another macronutrient that the cotton crop requires, which is important for increasing productivity.
Principais Deficiências
Main Deficiencies
Cotton’s Nitrogen Deficiency (N)
The importance of nitrogen (N): it is part of the composition of all amino acids and proteins, being also present in the chlorophyll molecule and in other pigments.
It acts in the formation and growth of the vegetative part, the flowering buds, regulates the plant cycle, increases productivity and improves the length, fiber resistance and micronaire index. Nitrogen (N) deficiency presents with the loss of the intensity of the green color throughout the plant, due to the reduction of chlorophyll.
The symptom appears, in the form of yellowing in the older leaves of the “basseiro”. The lack of nitrogen (N) reduces the growth speed of cotton, reduces the number and length of internodes and consequently reduces the number of vegetative and reproductive branches.
Cotton’s Phosphorus Deficiency (P)
The importance of phosphorus (P): involved in energy transfers in the plant, being of vital importance for protein synthesis, photosynthesis and sugar transformation.
It is a component of respiration and photosynthesis, as well as the phospholipids that make up plant membranes. It is also a component of nucleotides used in energy metabolism in plants (such as ATP) and in DNA and RNA. It stimulates the growth of the roots, being important for the flowering and development of the fruits.
Phosphorus (P) favors the maturation of bolls, accelerating their opening. Phosphorus (P) deficiency has the most evident effect, the general reduction in plant growth. It causes the reduction of photosynthesis, the accumulation and translocation of carbohydrates to cotton bolls. Plants develop very slowly, the older leaves become reddish and progress to drying; in addition, there may be reddening of the stem. In case of a more severe deficiency, flower buds may drop, apple size reduction and poor retention of the same, impacting in the reduction of productivity.
Cotton’s Potassium Deficiency (K)
The importance of potassium (K): it has an important role in the energy state of the plant, in the translocation and storage of assimilates (products resulting from photosynthesis).
It catalyzes the activity of more than 60 enzymes in the plant, and is also important for efficient water use. It plays a key role in plant development, production and fiber quality. Potassium (K) deficiency occurs with greater frequency and intensity in cotton than in most agronomic species, as the plant is inefficient in absorbing potassium.
The deficiency is characterized by interveinal chlorosis of the basswood leaves, followed by necrosis at the margins and shedding; as a consequence, there is a shortening of the cycle, poor boll formation, reduced productivity and fiber quality.
Cotton’s Calcium Deficiency (Ca)
The importance of calcium (Ca): Fundamental in maintaining the structural integrity of membranes and cell walls, in the process of cell division, in ionic absorption, in pollen grain germination and in pollen tube growth.
The presence in the soil solution is essential for the correct development of cotton roots. Calcium (Ca) deficiency is not common in the field.
Normally, the effects of soil acidity and the deficiency of other nutrients overcome or are expressed faster than the deficiency of this nutrient in the crops. Deficiency is characterized by reduced growth, curvature of leaf margins, petiole collapse, reduced flowering and fruiting, and falling apples.
Cotton’s Magnesium Deficiency (Mg)
The importance of magnesium (Mg): it is essential for photosynthesis; It is a component of chlorophyll, a green pigment, an active participant in the photosynthetic process and an activator of all phosphorylative enzymes, which are responsible for the incorporation and transfer of inorganic phosphorus – Pi.
Magnesium binds ATP or ADP to the enzyme. Magnesium (Mg) deficiency is characterized by slow cotton growth.
The initial symptoms appear on the leaves of the bass, as it is a nutrient with high mobility in the plant. It causes interveinal chlorosis, that is, the veins and adjacent areas remain green.
Cotton’s Sulfur Deficiency (S)
The importance of sulfur (S): It participates in essential amino acids: cystine, methionine and cysteine.
It is a constituent of several coenzymes, in addition to vitamins.
Sulfur (S) deficiency impairs photosynthesis, affecting productivity and fiber quality. Sulfur-deficient plants have reduced growth, emit few vegetative and reproductive branches and have yellow-green leaves on the tip.
Cotton’s Iron Deficiency (Fe)
The importance of iron (Fe): it plays an important role as a component of enzymes involved in electron transfer (redox reactions), such as cytochromes, and also catalyzes the biosynthesis of chlorophyll.
The cotton plant rarely shows symptoms of iron (Fe) deficiency, but it can be characterized by the fine interveinal chlorosis present in young leaves.
Cotton’s Manganese Deficiency (Mn)
The importance of manganese (Mn): it is essential for the synthesis of chlorophyll and its main function is related to the activation of enzymes.
Manganese (Mn) is needed to break down the water molecule, evolve O2 and allow the start of electron flow in photosynthesis.
The symptom of manganese (Mn) deficiency is characterized by interveinal chlorosis in young leaves, as manganese is poorly mobile in the plant.
Cotton’s Zinc Deficiency (Zn)
The importance of zinc (Zn): necessary for the processes of protein synthesis and detoxification of superoxide ions formed in cellular metabolism.
Zinc (Zn) deficiency is not common in the field, but can be identified in young leaves that have chlorosis and irregular margins.
Cotton’s Copper Deficiency (Cu)
The importance of copper (Cu): necessary for the processes of protein synthesis and detoxification of superoxide ions formed in cellular metabolism.
Copper (Cu) deficiency normally does not appear in the field, but can be identified by fine interveinal chlorosis, with leaf blade deformation in young leaves.
Cotton’s Boron Deficiency (B)
The importance of boron (B): It acts together with calcium in the regulation of the functioning of the membrane and cell wall, division and increase of cells, lignification of the cell wall, being essential for the formation of meristematic tissues.
It influences root development, nutrient absorption and pollen grain germination; participates in the metabolism and transport of carbohydrates through the formation of sugar-borate complexes, being important in the synthesis of proteins.
The symptoms of boron deficiency (B) appear initially with the yellowing of the leaves of the pointer; dark green concentric rings may appear on the petioles and stems, with internal necrosis of the medulla. There is also excessive fall of flower buds, flowers and even new fruits.
Fertilizantes Indicados
Indicated Fertilizers
Pragas do algodão
Pragas das raízes do algodoeiro,
pragas das folhas e hastes
pragas das estruturas frutíferas.
- Broca-da-raiz
Eutinobothrus brasiliensis - Percevejo-castanho
Scaptocoris castanea e S. brachiariae
- Lagarta-rosca
Agrotis ipsilon - Lagarta falsa-medideira
Chrysodeixis includens - Pulgão
Aphis gossypii - Mosca-branca
Bemisia tabaci e Bemisia tabaci biótipo B - Tripes
Frankliniella schultzei e Caliothrips brasiliensis - Ácaro-rajado
Tetranychus urticae - Ácaro-vermelho
Tetranychus ludeni - Ácaro-branco
Polyphagotarsonemus latus - Curuquerê-do-algodoeiro
Alabama argillacea
- Bicudo-do-algodoeiro
Anthonomus grandis - Lagarta-das-maçãs
Heliothis virescens - Lagarta spodoptera
Spodoptera frugiperda - Lagarta helicoverpa
Helicoverpa armigera - Lagarta-rosada
Pectinophora gossypiella - Percevejo-rajado
Horcias nobilellus - Percevejo-manchador
Dysdercus sp. - Percevejo-verde
Nezara viridula - Percevejo-marrom
Euschistus heros - Percevejo-verde-pequeno
Piezodorus guildinii
Tombamento
Entre os patógenos causadores de tombamento
podem-se destacar os fungos dos gêneros
Colletotrichum, Fusarium, Pythium e Rhizoctonia
(sendo este último o mais importante).
- Ramulose
Colletotrichum gossypii var. Cephalosporioides - Mancha angular
Xanthomonas axonopodis pv. Malvacearum - Mancha alvo ou mancha de corinéspora
Corynespora cassiicola - Mancha branca ou mancha de ramulária
Ramularia aréola
- Mancha-de-mirotécio
Myrothecium roridum - Manchas de alternária e estefilium
Alternaria sp e Stemphylium solani - Mofo branco
Sclerotinia sclerotiorum - Murcha de fusarium
Fusarium oxysporum f. sp. Vasinfectum
- Doença Azul
Doença de natureza virótica cujo agente causal ainda não foi descrito. A doença tem como vetor o pulgão Aphis gossypii. - Nematoides
Especialmente os do gênero Meloidogyne, Rotylenchus e Pratylenchus.