Spraying milk on cucumbers kills mildew

October 13, 1999

THE doorstep pint has the makings of an ideal fungicide for protecting organically grown cucumbers and other vegetables, according to researchers in Brazil. It attacks a mould known as powdery mildew, which is a major problem for organic farmers scrambling to meet the growing demand for chemical-free vegetables.

The mould, Sphaerotheca fuliginea, appears as a powdery white growth on the leaves of cucumbers and courgettes (zucchini). It damages the plants by causing the leaves to shrivel up. At present, only chemical fungicides are available.

Milk's fungicidal powers were discovered by Wagner Bettiol of the environmental laboratory of Embrapa, the Brazilian Agricultural Research Corporation, in Jaguariuna, north of São Paulo. Bettiol, who was looking for cheap ways to control plant pests, observed that byproducts from milk-processing factories killed powdery mildew on courgettes. So he decided to simply spray fresh milk on the plants to see if it had the same effect. To his surprise, he found that it did. In fact, spraying heavily infected plants twice a week with a mixture of one part cow's milk to nine parts water was at least as good at stopping mildew as the chemical fungicides fenarimol and benomyl, Bettiol discovered.

In many cases, milk was both faster and more effective. After two to three weeks of spraying with milk, the area of leaves infected was in some cases only a sixth or less of the area affected on plants treated with chemical fungicide (Crop Protection, vol 18, p 489). Bettiol says several organic growers in his region have successfully controlled less severe mildew infections on courgettes and cucumber by spraying once a week with 5 per cent milk solutions.

Bettiol is not yet sure why milk works so well, but he speculates that it helps the plants in two ways. Milk is known to kill some microorganisms. It also contains potassium phosphate, which boosts the plant's immune system and so may help it inhibit the mildew's growth.

"If this works, it could be very useful," says Rob Haward of the Soil Association, which sets standards for organic farming in Britain.
Author: Debora MacKenzie


New Scientist

Related Milk Articles from Brightsurf:

The "gold" in breast milk
Breast milk strengthens a child's immune system, supporting the intestinal flora.

Pasteurizing breast milk inactivates SARS-CoV-2
Pasteurizing breast milk using a common technique inactivates severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) making it safe for use, according to new research in CMAJ (Canadian Medical Association Journal). ttps://www.cmaj.ca/content/cmaj/early/2020/07/09/cmaj.201309.full.pdf

Milk lipids follow the evolution of mammals
Skoltech scientists conducted a study of milk lipids and described the unique features of human breast milk as compared to bovids, pigs, and closely related primates.

Raw milk may do more harm than good
Raw or unpasteurized cows' milk from U.S. retail stores can hold a huge amount of antimicrobial-resistant genes if left at room temperature, according to a new study from researchers at the University of California, Davis.

Milk pioneers: East African herders consumed milk 5,000 years ago
Animal milk was essential to east African herders at least 5,000 years ago, according to a new study.

Breast milk may help prevent sepsis in preemies
Researchers at Washington University School of Medicine in St. Louis and Mayo Clinic in Rochester, Minn., have found -- in newborn mice -- that a component of breast milk may help protect premature babies from developing life-threatening sepsis.

Drinking 1% rather than 2% milk accounts for 4.5 years of less aging in adults
A new study shows drinking low-fat milk -- both nonfat and 1% milk -- is significantly associated with less aging in adults.

Photoinitiators detected in human breast milk
Photoinitators (PIs) are compounds used in the ink of many types of food packaging.

Milk from teeth: Dental stem cells can generate milk-producing cells
Stem cells of the teeth can contribute to the regeneration of non-dental organs, namely mammary glands.

Micro-ribonucleic acid in milk:Health risk very unlikely
Ribonucleic acid (RNA) occurs in animal and plant cells and has many biological functions.

Read More: Milk News and Milk Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.