Chenopodium album is a wide spread annual weed and mostly found in cotton, wheat and safflower. Its local name is Bathu. Its English name is Lambs quarters. It has very strong Allelopathic effect on different field crops. An experiment was conducted using the RCBD factorial design on application of root and shoot extract of lambs quarter on safflower germination %age. Analysis of variance showed that type and part of weed (Chenopodium album) used for treatments had significant effects and also interaction effect on all studied germination attributes of safflower at 1% level. Treatment with distilled water, produced the highest seedling length, dry weight, germination percentage, coefficient of germination rate and germination time in comparison with weed extracts. Extract treatments did not germinate. Chenopodium album root extract and shoot extract decreased the seedling length by 54.71 and 62.24% and seedling dry weight by 52.5 and 78.18%. Germination time in control was 3 days. While germination time by treatment with C. album was 8 days.
The negative impact of c. album extracts on growth and germination of wheat, barley, corn, soybean, sugar beet, sunflower 7, celery, rapeseed and sorghum 1 has been proven. Germination and seedling establishment of corn, sugar beet, Trifolium alexandrium and Tritium pyramidal were reduced by Chenopodium album extract 10&%.Negative impacts on germination, growth and dry matter rate of soybean 26, wheat 2, cotton and barnyard grass 25 by C. Album extract have been reported.
Some researchers believe that seedling stage is most susceptible to Allelopathic compounds which can have strong effects on seedlings. This remarkable reduction of seedling growth can lead to the reduction of plant establishment and competition with weeds on environmental factors. Main effect of Allelopathic compounds is delaying of radicle and shoots growth 10. Phenolic compounds decrease ATP production by reducing the mitochondrial respiration. This leads to some physiological effects that reduce growth and dry matter accumulation in plant. Conclusion of germination can be related to changes of enzyme activities. Dysfunctionality in respiration leads to ATP energy restriction and decrease of germination and seedling growth. Flavonoids Existing in Chenopodium album are compounds which decrease seed germination by escaping of Energy broadcast 20. Allelopathic effects not only cause reduction but also postponement of germination which toughly affect competition between plants. Seedlings of smaller size might compete lesser with neighbors under undesirable conditions such as low soil moisture or fertilizer limitation 12. Weed extracts significantly decreased safflower height, root and shoot dry weight, root length, leaf area and biomass as compared with control treatment.
- album also decreases the dry root and shoots weight. Safflower root length was affected by weed root extracts greater than by shoot extracts, 72.4% by root and 56.47% by shoot extracts compared with control treatment. (F. Rezaie and M. Yarnia).
Another study was done on “Effect of Chenopodium Album Allelopathic Extract and Salicylic Acid Priming under Seed Aging Condition on Germination and Seedling Growth of Foeniculum vulgare Mill” Many researchers also have reported that priming enhances germination and emergence of weak or damaged seeds. Researchers have stated that priming increases the vigor of rice, corn, peas and soybeans seeds and lead to rapid setting up, early flowering and high yield. There is no noteworthy difference between control and 16 hours aging by Application of Allelopathic extracts but 32 hours aging compact germination. Seedling growth rate reduced by Allelopathic compound but aging effect was more than Allelopathic compound. Aging increased seed sensitivity to Allelopathic compound. Stopping germination may relate to change in enzyme activity that effect on transfer and storage compounds during germination. Water priming and salicylic acid increased germination rate.
This means that priming reduced the power of germination that reduced by allelopatic compounds. Because priming enhanced germination, seedling emergence and establishment and improved yield also and abridged time of germination. Seed priming also increases seed vigor and decreases losses from late planting. Rapid germination under effect of priming rising from synthesis of DNA, RNA and proteins.
This study demonstrated that Chenopodium album displayed allelopatic activity and influenced emergence and growth of Foeniculum vulgare. Germination percentage was less sensitive than seedling growth to allelopathy. Effects of Chenopodium album extract on shoot and root elongations and dry matter were variable. The pattern observed suggests a high ability of Chenopodium album to compete against weeds which can be an issue with potential agronomic consequences. The results indicate a different degree of sensitivity between seed aging, and suggest that if water resources limited during plant growth, which is common in Mediterranean areas, poor germination percentage, root development and dry matter accumulation of weeds may restrict the ability of weeds to cope with a water deficit and impair their ability to compete with Chenopodium album. Based on our results it seems that salinity resistance of Fennel seeds at germination stage will increase by treating seeds with on mm salicylic acid. This study is the first to demonstrate the allelopatic potential of Chenopodium album, one of the most valuable weeds in arid and semiarid areas, and the results can be the basis for establishment of long-term experiments to evaluate allelopathy under field conditions.
Jabir Riaz*,Imran Ramzan1, and Asrar Masood3.
Author * & Co- Author1 Department of Agronomy, University of Agriculture Faisalabad
3Department of Soil and Environmental Sciences, University of Agriculture Faisalabad