Manganese (Mn) deficiency symptoms

Manganese (Mn) deficiency symptoms.

• Plants exhibit “comb-tooth” leaf chlorosis and the presence of fungus- Deightoniella torulosa in the chlorotic areas.

• The chlorosis starts from the leaf margins and spreads along the veins towards the midrib with interveinal areas remaining green, hence the comb-tooth appearance.

• Leaves desiccate prematurely causing poor fruit development.

• Normal size bunch is produced by the plant but the fruits are covered with black spots.

Control Measures:

a.      Spray Manganese sulphate @ 2 g/l of water ( Neutralized with lime)once a week for two weeks.

Photos courtasy: TNAU, Coimbatore, Tamilnadu, India.

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Posted in: 35. Manganese (Mn) deficiency symptoms

Calcium (Ca) deficiency symptoms

Calcium (Ca) deficiency symptoms:

• Young leaves show interveinal chlorosis near the margins and towards the tip. 
• When these chlorotic patches die they create a serrated necrosis along the leaf margin. 
• A temporary shortage of calcium causes the “spike leaf” symptoms in the field in which the lamina of new leaves is deformed or almost absent with thickened lateral veins near the mid-rib and deficient root system which is susceptible to rot. 
• Fruit quality is inferior and the peel splits when the fruit is ripe.

(Boron and Calcium deficiency symptoms tend to overlap. So see Boron deficiency pictures also).

Picture 1: Ca deficiency-Early foliar symptom - 
Yellow stripes parallel to leaf midrib.

         
Picture 2:  Ca deficiency-Early foliar symptom - 
Yellow stripes parallel to leaf midrib.

        Picture 3: Early foliar symptom of Calcium and Boron deficiency -           WRINKLED LEAF.

        

          Picture 4: Boron & Calcium deficiency - deformed and whitish heart leaf. 

        
Picture 5: Boron and Calcium deficiency - "SPIKE LEAF" (in which the        lamina of new leaves is deformed or almost absent). 

 

(Photos credit: ctahr, Hawaii)

Control Measures:

         

a.     Drip fertigation of Calcium Nitrate (CaNo3) @ 4 kg/1000 plants every 4^th day upto 5^th month.

                                                (OR)

b.     Manual application of Calcium nitrate (CN)) @ 40g/plant per month upto 5^th month and if necessary till finger development. Application of CN  provides calcium as well as nitrogen (15.5-0-0 + 19% Ca) to the soil, therefore quantity of nitrogen needs to be adjusted with the total nitrogen requirement of the soil.

The picture below shows a plant affected due to Calcium and Boron deficiency and the subsequent recovery after the remedial measures taken as under:

Step 1: Drenching the growing shoot (by applying inside the emerging unfurled funnel shaped leaf) with 100 ml of foliar grade boron rich micronutrient solution.

Step 2: Fertigation of Calcium Nitrate @ 20 gm / plant (in 2 split doses).

Note: If the deficiency is severe, 3 to 4 foliar applications of micronutrients have to be given to the crop up to 7 months along with fertigation of Calcium Nitrate @ 75 gm / plant in 5 to 7 split doses.

 

Sources of Calcium:

Lime

Soil amendment which is commonly used to raise the pH of the soil.

Calcium Carbonate

Approximately 38% Ca, depending upon its source

A common liming material, calcium carbonate also supplies calcium to the soil.

Dolomite

22% Ca and 12% Mg, depending upon the dolomite source

In addition to raising the pH, dolomite is a source of calcium and magnesium.

Gypsum

23% Ca and 19% S

Unlike liming materials, gypsum does not increase the soil pH.

In addition to providing calcium and sulfur, gypsum may be used to correct soil physical problems and/or aluminum toxicities.

Calcium nitrate

15% N and 20% Ca

Calcium nitrate is very soluble in water.

Superphosphates

Single (SSP)

18-21% Ca

SSP supplies both calcium and phosphate.

Triple (TSP)

12-14% Ca

Like SSP, TSP supplies both calcium and phosphate

Regards,
A.Vishnu Sankar

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Posted in: 30. Calcium (Ca) deficiency symptoms

CONTIGENCY PLANS

(This useful article is published by NRCB, Trichy for farmers ready reference).

CONTIGENCY PLANS .  .  .  .  . Overcoming soil sodicity problem in banana Due to salinity and sodicity of soil, the banana plants may suffer from marginal chlorosis and necrosis of older leaves, lesser proliferation of roots and an yield reduction by about 30%. This problem may be rectified by applying 0.5 kg of gypsum + 15 kg of FYM along with 120 % recommended potassium per plant. The water drainage facility of the land should be improved to leach down the excess sodium and salts. Overcoming flood damage in banana Open deep trenches between the plant rows for improving the drainage condition of the land. Give foliar spray of 2% potassium sulphate. After 15 days, give another foliar spray of 1% potassium nitrate. At the bunch development stage, give 2% potassium sulphate spray on bunch, two times with 15 day interval. During flood, the possibility of outbreak of Sigatoka leaf spot is more. As a prophylactic measure, give 0.1 per cent Propiconozole, 0.2 per cent Carbendazim and 0.25 per cent Mancozeb foliar sprays with 15 day intervals between each spray. Overcoming wind damage in banana Banana crop can not tolerate the wind speed of even 30 km/hr. Banana being a shallow rooted crop requires proper propping with bamboo or casurina poles to avoid lodging during windy seasons. The supporting poles should be tied against the peduncle of developing bunches, so that it protects the plant from lodging during windy seasons and bears whole weight of developing bunch. Overcoming the stem weevil problem The appearance of small holes and oozing out of gummy substances and fecal matter reveals the presence of stem weevil damage in banana. Give monochrotophos (150ml monochrotophos + 350ml water) injection. If ratooning is adopted, remove and destroy the mother plants after bunch harvest. Overcoming the chilling injury during winter Banana growing regions, where the night temperature is below 5oC during winter, protection of bunches with 100 gauge polythene sleeves of 6% ventilation is very essential. Overcoming the Erwinia rot During summer, high soil temperature injures the pseudostem tissues, which are in touch with soil. Through these injuries, Erwinia bacteria may enter the plant and cause rotting. To avoid this, drench the soil around the plant with 2% bleaching powder solution. Overcoming the Wilt disease The varieties like Karpuravalli, Rasthali, Ney Poovan and Monthan are susceptible to Panama Wilt. The soil around the wilt-affected plant should be drenched with 2% carbendazim solution. Or cabendazim filled gelatin capsule should be applied into the corm. The affected plant should be uprooted and destroyed out of the field. After uprooting, about 3kg of lime should be applied to the soil. The implements used in affected plants should be disinfected by spirit before using them in healthy plants. Contingency plan against natural calamities - Drought The water scarcity situation during summer months could be overcome by adopting drip irrigation. Use of plant waste mulches viz., banana leaf mulches, sugarcane trashes, paddy straw mulches around the plants conserves soil moisture and also promotes production of more feeder roots. Protecting the peduncle from sun scorching The fruit peduncle on exposure to sunlight suffers from sun scorching, which subsequently makes entry for pathogens that leads to rottig, poor uneven finger filling and ultimately breaking of the peduncle along with the bunch. Hence, the peducle should be fully covered using the 'boot leaf' that emerges just before the bunch. Propping / giving mechanical support to the plants against the wind By giving 'Double pole support' using bamboo or casuarina poles, the plants can be protected from uprooting by heavy winds during the hot months (April/May) or during summer showers locally called as 'Chiththirai chuli' and during monsoon winds.

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Posted in: 19. Contigency plans

CALENDAR OF AGRICULTURAL OPERATIONS FOR BANANA:

(This useful article is published by NRCB, Trichy for farmers ready reference).

CALENDAR OF AGRICULTURAL OPERATIONS FOR BANANA:

Preparation of land: Plough the land thoroughly at least for 3-4 times and add about 10 tonnes of well rotten FYM or Compost during last plough and mix it well or add 10-15 kg FYM/ Compost per pit  of 60x60x60 cm dimension. Selection of Suckers: Select ‘Sword Suckers’ with broad corm with narrow sword like leaves, from viral, fungal and bacterial disease free mother plants.  The suckers should be 3-5 months old, uniform in size, weighing 1-1.5 kg for Nendran, Rasthali, Ney Poovan and Poovan banana varieties. For long duration varieties like Karpuravalli and Red Banana, slightly big suckers weighing 1.5-2.0 kg should be used. For planting of ‘Tissue Culture’ plants, the secondary hardened plant should be about 30 cm tall,  5 cm girth with at least five fully opened healthy leaves and true to type.   Sucker Treatment and planting: ·         The selected suckers should be ‘pared’ by trimming of all the roots along with surface layers superficially to remove any rotten portion of the corm. ·         Dip the pared suckers in 0.2% Carbendazim (2g/litre of water) solution for about 15 –20 minutes as a prophylactic measure against Fusarium wilt disease. ·         Keep the treated suckers in shade overnight before planting. Plant the suckers in the center of the pit and press the soil around the suckers firmly. ·         Apply 40 g of Carbofuron granules per pit to protect the plants against nematode attack and irrigate the field thoroughly. In case of tissue culture plants, one week before planting apply 10 g  Carbofuron and 1.0 % bleaching powder or 0.2 % Emissan in 100 ml water as drench into  the polythene bags to protect against nematode infestation and bacterial rot (Erwinia Rot) disease respectively.

CALENDAR OF OPERATIONS.....

During First month ·                     The soil around the plants should be pressed firmly for better and quick establishment of the plants. ·                     Wherever necessary, ‘Gap Filling’ should be done to replace the un- sprouted as well as rotten suckers. Seeds of green manure crops viz., cowpea or sunnhemp be sown. ·                     For additional income and also for effective land use efficiency, short duration crops such as onion, green gram, black gram, beans, radish, greens, marigold and short duration vegetables can be grown as intercrop. ·                     Tomato, chilly and cucurbits should not be grown as intercrop since these crops harbour nematodes and aphids, which act as vector of virus spread.

Second Month ·                     Green manures viz., cowpea or sunnhemp should be ploughed back in to the soil at flowering stage or about 40 days after sowing. ·                     Slight digging and earthing up to keep the weeds under control. ·                     For Fusarium wilt susceptible varieties like Rasthali, Karpuravalli, Ney Poovan, Monthan and Pachanadan,  drench the soil around the plant with 0.2% Carbendazim as a prophylactic measure, or  ·                     Apply 30g Trichoderma viride or Pseudomonas flourescense  along with FYM/compost 1 kg in the soil around the plant as a prophylactic measure for the  control of wilt disease.

Third Month ·                     Application of 40g of Carbofuron to control nematodes. ·                     Digging and weeding.  ·                     Application of first dose of fertilizers @ 100:300:100 g Urea, Super Phosphate and MOP per plant in basins made about 30 cm away from the plant.

Fourth Month ·                     Application of Azospirillum and phosphobacteria @ 30 g and Trichoderma viride  @ 30g along with 5-10 kg FYM plant-1. ·                     There should a gap of minimum 2-3 weeks between the application of chemical fertilizers and biofertilizers. ·                     Periodical removal of side suckers by cutting them above the ground level and pouring 2 ml kerosene at the central core of the sucker. ·                     If any virus affected plants are noticed in the field, remove and destroy it immediately and spray with any systemic insecticide to kill the insect vectors which spread the virus.

Fifth Month ·                     Application of second dose of fertilizers @ 150:150 g Urea and MOP+ 300g neemcake per plant in the basins made about 45 cm away from the plant. ·                     Removal of dried leaves. ·                     Digging and weeding. ·                     To cater the micronutrient need of the plant and to correct their deficiency, apply 50g  agricultural lime and 25g  magnesium sulphate per plant. ·                     For Fusarium wilt susceptible varieties like Rasthali, Karpuravalli, Ney Poovan, Monthan and Pachanadan drench the soil around the plant with 0.2% Carbendazim as a prophylactic measure.  ·                     To prevent the egg laying and further attack of stem weevil, spray ‘Neemosol’ @12.5ml/litre or Chlorpyriphos @ 2.5ml/litre on the stem especially in Nendran, Red banana, Karpuravalli and Monthan varieties. ·         To monitor the corm and stem weevil, 2 ft long longitudinal stem trap @40 traps/acre can be placed at different places. The collected weevils are to be killed using kerosene. ·         Keep the banana fields as well as surrounding areas weed free and spray systemic insecticides to control the insect vectors.

Sixth Month ·                     Digging and earthing up of soil around the plant. ·                     Removal of the dried and diseased leaves and spraying of 0.1% Propiconazol (TILT) by thoroughly covering both the surfaces adding wetting agent with the spray fluid especially during winter and cool months for control of Sigatoka leaf spot diseases. ·                     Yellowing of leaves which is a symptom of iron deficiency, spray 0.5% ferrous sulphate + 1.0% urea added with wetting agent on the leaves especially in high pH >8.5 and Calcareous soils. ·                     To correct the deficiency of zinc, spray 0.5% zinc sulphate solution along with wetting agent. ·                     Foliar application of 0.5 Borax is recommended to correct the  deficiency. ·                     Apply 30g Trichoderma viride or Pseudomonas flourescense in the soil around the plant as a prophylactic measure to control the wilt disease. ·                     For controlling the stem weevil attack, using ‘Banana Injector’,  inject 2ml of Monocrotophos (150 ml  Monocrotophos mixed in 350 ml of water) at 2 and 4 feet height on opposite direction.

Seventh Month ·                     Application of third dose of fertilizers @ 150:150 g Urea and MOP per plant in the basins made about 60 cm away from the plant. ·                     Removal of the dried and diseased leaves and spraying of 0.1% Carbendazim or Calixin by thoroughly covering both the surfaces along with wetting agent. ·                     Periodical removal of side suckers by cutting them above the ground level, scoop the core  and pour 2 ml kerosene in the core. ·                     Injection of 2ml of Monocrotophos using ‘Banana Injector’ at 2 and 4 feet height  for the control of stem weevil.

Eighth Month ·                     After flowering, only one healthy side sucker should be allowed for first ratoon  and the remaining suckers should be killed using kerosene or uprooted. ·                     Spraying of 0.1%  Indofil by thoroughly covering both the surfaces. ·                     After the emergence of the last hand, the male bud has to be removed leaving about 15 cm stalk from the last hand. ·                     To prevent ‘cigar end rot’ disease, remove the pistil and perianth carefully from the fully emerged fingers and spray the bunch with Indofil M-45 @ 2.5 ml/litre. ·                     Spray 2% Potassium Sulphate (20g/litre of water) solution with surfactant by thoroughly drenching the bunch and cover the bunch with 100 gauge thick white or blue polythene sleeves having 6% ventilation.

Ninth Month: ·                   Thirty days after the first spray, give a second spray of 2% Potassium Sulphate (20g/litre of water) solution with surfactant by thoroughly drenching the bunch. ·                      Provide casuarina pole or bamboo support to the plants for tall and heavy bearing bunches.

Plant population under different planting systems S.No  Method of Planting Spacing (m) Plant Population/ ha 1    CONVENTIONAL PLANTING     i) Dwarf Cavendish  1.5x1.5 4440     ii) Robusta and Nendran 1.8x1.8 3080     iii) Rasthali, Poovan, Karpuravalli, Monthan 2.1x2.1 2260 2. HIGH DENSITY PLANTING            a) Paired row planting system i) Dwarf Cavendish ii) Robusta, Grand Naine, Poovan, Rasthali and Ney Poovan 1.2x1.2x2.0 1.5x1.5x2.0 5200 3800     b) 3 suckers/hill (Robusta, Nendran) 1.8x3.6 4500

Drip Water requirement at different growth stages of banana Sl. Crop growth stage Duration (weeks) Quantity of Water (litre/plant) 1. After planting / Ratoon 1-4 Flood irrigation 2. Juvenile phase 5-9 8-10 3. Critical growth stage 10-19 12 4. Flower bud differentiation stage 20-32 16-20 5. Shooting stage 33-37 20 and above* 6. Bunch development stage 38-50 20 and above8             * Depending on the season

Weekly Fertigation Schedule for banana (g/ plant / application)   Weeks after Planting   Urea Total (g/plant) MOP Total (g/plant) 9 to 18 week (10 weeks) 15 150 8.0 80 19 to 30 week (12 weeks) 10 120 10 120 31 to 40 week (10 weeks) 7.0 70 12 120 41 to 46 week (5 weeks) Nil Nil 10 50 Total ---- 340 ---- 375

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Posted in: 17. Calendar of cultivation