What are the comprehensive control measures for root-knot nematode disease in ginger?

Ginger is the fresh rhizome of the perennial herbaceous plant ginger (Zingiber officinale) of the Zingiberaceae family, with a height of 40-100 cm. Its other names include ginger root, bai la yun, gou zhuang zhi, yin di xin, yan liang xiao zi, fresh ginger, and honey-roasted ginger. The rhizome (dried ginger), cork layer (ginger peel), and leaves (ginger leaves) can all be used as medicine. In traditional Chinese medicine, ginger has effects such as dispersing, stopping vomiting, and relieving cough.

The culinary value of ginger

It contains volatile oil, mainly gingerol, zingiberene, phellandrene, citral, linalool, etc.; it also contains the pungent component gingerol, which decomposes to produce gingerone, zingerone, etc. In addition, it contains asparagine, glutamic acid, aspartic acid, serine, glycine, threonine, alanine, etc. Chewing ginger in the mouth can cause blood pressure to rise. Gingerol has a stimulating effect on the oral and gastric mucosa, can promote the secretion of digestive juices, and increases appetite. It can increase intestinal tension, rhythm, and peristalsis. It has a peripheral antiemetic effect, with the active components being a mixture of gingerone and zingerone. It has an excitatory effect on the respiratory and vasomotor centers and can promote blood circulation. In in vitro experiments, it has a significant inhibitory effect on Salmonella typhi and Vibrio cholerae.

Morphological characteristics of ginger

Perennial root herb. The rhizome is fleshy, thick, flat, with an aromatic and pungent taste. Leaves are arranged in rows, lanceolate to linear-lanceolate, 15-30 cm long, about 2 cm wide, gradually pointed at the tip and gradually narrowed at the base, smooth and hairless, with a stem-clasping leaf sheath; sessile.

The flower stem is erect, covered with imbricate, loosely arranged scales; the spike inflorescence is ovate to elliptical, about 5 cm long and about 2.5 cm wide; the bracts are ovate, light green; the flowers are dense, about 2.5 cm long, sharply pointed at the tip; the calyx is shortly tubular; the corolla is 3-lobed, the lobes lanceolate, yellow, the lip is shorter, oblong-obovate, light purple, with yellow-white spots, and the lower part has small lobes on both sides; there is 1 stamen, protruding, the ovary is inferior; the style is filiform, light purple, and the stigma is radiate. The capsule is oblong and swollen, about 2.5 cm, and the flowering period is June-August.

Comprehensive control measures for root-knot nematode disease in ginger

Root-knot nematode disease in ginger is commonly known as ginger scab disease or ginger scale insect. In recent years, this disease has occurred in Laiwu, Ju County, Anqiu, and other places in Shandong. With continuous cropping and large-scale cultivation of ginger, this disease has shown a trend of increasing damage and expanding spread, and in some areas it has risen to become the second largest disease after ginger blast, greatly affecting ginger production and causing severely affected ginger to lose its edible value.

Occurrence of root-knot nematode disease in ginger:

Ginger can be affected from the seedling stage to the mature plant stage. Diseased plants can produce root knots of varying sizes on the roots and rhizomes. The root knots are generally the size of a bean grain, sometimes connected in strings. They are initially yellowish-white protrusions, later gradually turning brown, blister-like, rupturing and rotting. Because the roots are damaged, the absorption function is affected, growth is slow, the leaves are small, the leaf color is dark green, the stem is short, and branching is small. It can become visible from early to mid-July, and by around mid-to-late August the plants may be about 50% shorter than normal plants, but the plants rarely die.

Comprehensive control measures for root-knot nematode disease in ginger:

(1) Practice crop rotation. It is best to rotate with gramineous crops for 2-3 years, which can significantly reduce the disease.

(2) Select disease- and pest-free seed ginger and plow the soil deeply.

(3) Soil disinfection. Chemicals such as ethylene dibromide and methyl bromide can be applied 2-3 weeks before planting at a depth of 13-20 cm below the soil surface. The soil should be kept moist before application, and compacted after application to achieve the purpose of fumigating nematodes.

(4) Chemical control. Apply nematicides at planting time or from mid-to-late July to early August, depending on the disease condition, by furrow application or hole application. Nematicides include contact nematicides such as 10% ethoprophos, and systemic nematicides such as aldicarb, carbofuran, fensulfothion, fenamiphos, etc.

(5) Biological control. Strengthening cultivation management, removing diseased residues for centralized treatment, and adopting measures such as reasonable fertilization and irrigation can reduce the disease.