Difference in crop protection use in potatoes

The food sector compared with potatoes for industrial use - A Polish market overview

At present, in Poland, potatoes are grown mainly for consumption or as a raw material for the food processing industry (food and starch). The importance of potatoes’ for the animal feed sector has declined in favour of cereals and maize. The ultimate use of potatoes’ impacts decisions on variety selection, the application of fertiliser, and the use of mechanical and/or chemical crop protection usage.

Potato crops are highly vulnerable to weed infestation resulting from slow growth at the early stages of development and the crop’s specific requirement for wide spacing between rows. The control of weeds consists of both mechanical and chemical control methods. Recent Kleffmann Group survey data shows that the proportion of mechanical versus chemical treatment methods varies considerably according to the ultimate market for the potato crop.

For potato crops destined for the food sector, mechanical treatment plays a significant role in weed control and are the preferred method of weed control in a dry season. In 2016, Kleffmann Group research recorded that on 71% of the area of potatoes grown for food consumption, weed control was carried out mechanically, either as the only weed treatment method used, 19% of the total area, or, more commonly, as part of a programme consisting of both a chemical herbicide application and mechanical treatment, 52% of the total area. In 2016, just 21% of the area of potatoes for the food sector was treated with chemical, herbicide treatment alone. In contrast, weed treatment in potatoes grown for industrial use, is more widely by chemical herbicide application alone (55% of the area grown in 2016), and to a lesser extent by combining both chemical and mechanical control (37% of area grown in 2016). There does appear to be a move away from a total reliance on mechanical weed control, in potatoes grown either for food or industrial use in recent years.

Graph 1: The share of area treated with mechanical method and/or a herbicide. Source: amis®.

Graph 2: The average number of herbicide treatments per hectare. Source: amis®.

Graph 3: The average cost of herbicide protection (zł/ha). Source: amis®.

The intensity of chemical weed control is very similar, whether the crop is for food or industrial use. On average potatoes for food consumption are treated with 1,2 herbicide applications, whereas industrial potatoes are treated with 1,3.

Herbicide application in potatoes is carried out post emergence, when plants are 10 cm to 15 cm high. A second application is made by those who use a split dose of herbicides. Although the number of treatments is similar regardless of the use of the potato crop, the cost of herbicide protection is different. For potatoes for the food sector the cost of chemical herbicide is circa 156 zł (approx. 37,14 Euro) per hectare, and for industrial potatoes - 181 zł (approx. 43,10 Euro). This higher herbicide cost is a result of using higher dose rates. There has been little change in terms of the programme of herbicide usage over the last 6 years.

The most important diseases that threaten potatoes are potato blight and alternaria, either may cause a significant reduction or even complete loss of yield, it is therefore essential to combat these diseases. Kleffmann Group survey data shows that the intensity of fungicide applications varies considerably between the programmes used in potatoes for food use as opposed to industrial use. Potatoes for food use are, on average, treated with 2,4 applications of fungicide, whereas industrial potatoes are treated with 4,5 applications, on average. The average number of fungicide treatments in industrial use potatoes increased in 2016 compared to the two previous years, due to adverse weather conditions. There has been no notable change in the number of applications of fungicide in potatoes for food usage over the last 6 years of Kleffmann Group survey data reporting.

There is a direct relationship between the number of fungicide treatments and the cost of fungicide treatment. The average cost of fungicide treatment in potatoes for the food sector is 284 zł (approx. 67,62 Euro), and for potatoes, for industrial use, it is nearly twice as high, at 520 zł (approx. 123,81 Euro).

Graph 4: The average number of fungicide treatments per hectare. Source: amis®.

Graph 5: The average cost of fungicide protection (zł/ha). Source: amis®.

Graph 6: The average number of insecticide treatments per hectare. Source: amis®.

In addition to disease, the other serious risk for potato crops is damage by pest infestation, particularly Colorado potato beetle. Kleffmann Group surveys show that on average 1,4 treatments against pests are carried out regardless of the crops end’ use. Growers typically make a single insecticide treatment and select a product that effectively controls both larvae and adult beetles. A proportion of farmers will then carry out a second treatment if potato beetles attack again or if some other pest threatens their potato crop. Regarding the cost of pest control, it has been stable at circa. 58 zł (approx. 13,81 Euro)  regardless of potatoes’ use.

Author

Ewa Solińska

Project Manager Ad Hoc

Kleffmann Group Polska