Sweet Potato

Nutrients
Common Pests
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Nutrients

Crop Stage Images
Period of Doses		Pre-sowing Doses	After 30 Days
Nutrients (Kg/ha)	N	45	45
	P	60	–
	K	90	–

Deficiency of Nutrients:

Nutrients	Nitrogen (N)	Phosphorus (P)	Potassium (K)	Calcium (Ca)
Nutrients Deficiency
Deficiency Symptoms	1. Deficiency of N causes dramatic reductions in the growth of sweet potato plants and yet it is not easily recognised in the field. 2. General symptoms are a uniform light green chlorosis of the leaves, and slow growth resulting in a delayed or sparse ground cover. 3. These symptoms may be obvious in comparison with healthy plants, but less apparent in a uniform crop.	1. The first sign of P deficiency is usually the premature senescence of older leaves. 2. Yellowing may spread from discrete interveinal patches, which typically become cleared of anthocyanin pigment, or may be more general, but often affecting one half of the blade more than the other. 3. In this case, the chlorotic areas may appear orange or red due to the overlying anthocyanin pigments.	1. K deficiency can cause substantial growth reduction before specific symptoms develop. 2. In the field, symptoms often develop after two to three months, when the expanding storage roots begin to place increased demand on K supplies. 3. Brown necrotic lesions develop within the chlorotic zones and eventually spread to cover the entire leaf blade.	1. The primary symptom of Ca deficiency is the development of necrotic tissue on young leaves. 2. The necrosis usually begins along the lateral margins and extends inward mainly in interveinal tissue Necrotic tissue is mid to dark brown and brittle. 3. Necrosis is not usually preceded by localised chlorosis, although the leaves may be uniformly paler than normal.

Nutrients

Nitrogen (N)

Phosphorus (P)

Potassium (K)

Calcium (Ca)

Nutrients Deficiency

Deficiency Symptoms

1. Deficiency of N causes dramatic reductions in the growth of sweet potato plants and yet it is not easily recognised in the field.

2. General symptoms are a uniform light green chlorosis of the leaves, and slow growth resulting in a delayed or sparse ground cover.

3. These symptoms may be obvious in comparison with healthy plants, but less apparent in a uniform crop.

1. The first sign of P deficiency is usually the premature senescence of older leaves.

2. Yellowing may spread from discrete interveinal patches,
which typically become cleared of anthocyanin pigment, or may be more general, but often affecting one half of the blade more than the other.

3. In this case, the chlorotic areas may appear orange or red due to the overlying anthocyanin pigments.

1. K deficiency can cause substantial growth reduction before specific symptoms develop.

2. In the field, symptoms often develop after two to three months, when the expanding storage roots begin to place increased demand on K supplies.

3. Brown necrotic lesions develop within the chlorotic zones and eventually spread to cover the entire leaf blade.

1. The primary symptom of Ca deficiency is the development of necrotic tissue on young leaves.

2. The necrosis usually begins along the lateral margins and extends inward mainly in interveinal tissue
Necrotic tissue is mid to dark brown and brittle.

3. Necrosis is not usually preceded by localised chlorosis, although the leaves may be uniformly paler than normal.

Nutrients	Sulphur (S)	Magnesium (Mg)	Iron (Fe)	Boron (B)
Nutrients Deficiency
Deficiency Symptoms	1. Sulfur deficiency results in a uniform pale green chlorosis throughout the plant. 2. Veins do not retain a green colour, and in many cases, they may be more chlorotic than the interveinal tissue. 3. In which young leaves are normally green (ie. lacking red pigmentation), the youngest leaves may appear chlorotic earlier or more severely than mature leaves. 4. This is not obvious in cultivars with red or purple tips.	1. An Mg-deficient crop will tend to have a pale overall colour. 2. The earliest specific symptom of Mg deficiency is interveinal chlorosis of older leaves. 3. Typically, the main veins retain a relatively broad margin of dark green tissue, but the minor veins are less well defined, resulting in radial bands of pale tissue between the main veins.	1. The distinctive symptom of Fe deficiency is chlorosis of the youngest leaves. 2. Yellow interveinal chlorosis develops, which is characterised by a sharply contrasting green network of veins. 3. However, as the condition becomes more severe, the chlorosis becomes white and the veins may lose their green colour. 4. If young leaves are normally purple, they become pink as a result of Fe deficiency.	1. Boron deficiency affects actively growing tissue, both of the shoots and roots. 2. The first sign is usually a thickening of young leaves. 3. The leaves and stem near the shoot tip are brittle and break easily when bent. 4. Young leaves are usually paler than the older leaves but the extent and pattern of chlorosis are variable.

Nutrients

Sulphur (S)

Magnesium (Mg)

Iron (Fe)

Boron (B)

Nutrients Deficiency

Deficiency Symptoms

1. Sulfur deficiency results in a uniform pale green chlorosis throughout the plant.

2. Veins do not retain a green colour, and in many cases, they may be more chlorotic than the interveinal tissue.

3. In which young leaves are normally green (ie. lacking red pigmentation), the youngest leaves may appear chlorotic earlier or more severely than mature leaves.

4. This is not obvious in cultivars with red or purple tips.

1. An Mg-deficient crop will tend to have a pale overall colour.

2. The earliest specific symptom of Mg deficiency is interveinal chlorosis of older leaves.

3. Typically, the main veins retain a relatively broad margin of dark green tissue, but the minor veins are less well defined, resulting in radial bands of pale tissue between the main veins.

1. The distinctive symptom of Fe deficiency is chlorosis of the youngest leaves.

2. Yellow interveinal chlorosis develops, which is characterised by a sharply contrasting green network of veins.

3. However, as the condition becomes more severe, the chlorosis becomes white and the veins may lose their green colour.

4. If young leaves are normally purple, they become pink as a result of Fe deficiency.

1. Boron deficiency affects actively growing tissue, both of the shoots and roots.

2. The first sign is usually a thickening of young leaves.

3. The leaves and stem near the shoot tip are brittle and break easily when bent.

4. Young leaves are usually paler than the older leaves but the extent and pattern of chlorosis are variable.

Common Pests

Sweet Potato WeevilSweet Potato Leaf Eating Caterpillar / Sphinx Caterpillar

Images Of Pest Life cycle:
Stages:	Egg	Larvae	Pupae	Adult
Mark Of Identification:	100-200, on the tubers & stems of vines by making small cavities.	Small, legless & pale yellow in colour with a brown head.	Pupation in the Larva larval burrows in vines.	Small, ant-like, 6-8 mm long. Head is bluish brown, thorax & legs brownish red and antenna bright red in colour.
Life Cycle:	5-7 Days.	8 Days.	15 Days.	10 Days.