Saeid Shiukhi, Mahmoud Raeini, Vida Chalavi Sari Agricultural - PowerPoint PPT Presentation

COLORED PLASTIC MULCH MICROCLIMATES AFFECT STRAWBERRY FRUIT YIELD AND QUALITY Saeid Shiukhi, Mahmoud Raeini, Vida Chalavi Sari Agricultural Sciences and Natural Resources University IRAN

ENVIRONMENTAL FACTORS AFFECTING PLANT GROWTH & DEVELOPMENT Light Temperature Water Gases

Pla lant t Lig ight Envi vironment PAR (Photosynthetically Active Radiation) 400-700nm

Photoreceptors A) Photosynthesis a. Chlorophylls b. Carotenoids  Energy Transfer  Light ----> Chemical Energy B) Photomorphogenesis a. Red / Far-Red Reversible b. Phytochrome

Pla lant t Lig ight Envi vironment Photosynthesis Chlorophyll a & b : absorb blue light (450 nm), red light (680-700 ) Blue Light Sensitive System Red Light Sensitive System

Pla lant t Lig ight Envi vironment Photomorphogenesis Lig ight det etermines or organs mor orphology, whic ich is is co controlled pigment p hytochrome by by pig Phytochrome absorbs red (660nm) and far- red (730nm) wavelenghs Pigment form changes by absorbing each wavelength

Pla lant t Lig ight Envi vironment Phytochrome Light Absorption 650 650-670 0 nm nm 705 705-740 nm

Colored Mulches  Due to different light wave reflections by colored plastic mulches, they affect plants in different ways  The phytochrome protein is an enzyme that is very receptive to surrounding color, and has an effect on where carbon is partitioned to in plants  Phytochrome acts as a competitive tool for plants. When other plants are close by, plants “sense” the presence because of what light rays they receive

Phytochrome  Dark Red Dark P ------->Pr ----------------> Pfr ------> Response <--------------- Far-Red  Molecular Switch  Pfr - Active Form

Phytochrome Structure

Energy Balance over Plastic Mulch 4 4 4              R ( Q q )( 1 r ) T T T n sky surounding objects mulch Solar Short Long Wave Radiation Wave Radiation      R n H E S P 4      ( Q q ) r T mulch Reflected Short Wave Outgoing Long Wave Radiation from mulch Radiation from Mulch

Experimental Design Complete Randomized Block Design 1) Red Plastic Mulch 2) Black Plastic Treatments: 3) White Plastic 4) Conventional Method 3 Replication: 5 rows on each raised bed Conducted in IRAN, Caspian Sea Province of Mazandaran, From Fall 2010 to Spring 2011

Thermal & Radiation Properties of Plastic Mulches    r r r r white red soil black

Experiment view

Treatments fruit view White Red Plastic Control Black

Fruit Size Categories 1, > 35 mm 2, 25 - 35 mm 3, 22 - 25 mm 4, < 22, deformed rotted - 25 m

Soil te temperatures

Fruit Wei eight, t, Harvest t Tim ime & Mulc lches

Tota tal Fruit it Wei eight t ove ver dif iffe ferent t Mulc lches

Tota tal Fruit it Numbers ove ver dif iffe ferent Mulc lches

Graded Fruit t Numbers ove ver dif iffe ferent Mulc lches

Mean to tota tal l Graded Fruit t Numbers alo long Treatments

ts Str trawberry Phyto tochmical Conte tents Experimental treatments Control White plastic Black Plastic Red Plastic Anthocyanin 25.3 c 64.3 ab 59.3 b 84.5 a Flavonoid 7.43 ± 0.30 b 7.63 ± 0.54 b 7.73 ± 0.15 ab 8.57 ± 0.56 a IC 50 ** 3.10 ± 1.17 ab 2.83 ± 0.80 b 3.97 ± 1.17 a 3.37 ± 1.35 ab Phenolic 53.0 ± 9.2 a 55.7 ± 4.8 a 54.0 ± 0.8 a 54.1 ± 8.9 a compounds

Conclusion: The results of this research indicate that plastic mulches improve: 1) Fruit yield 2) Fruit size 3) Fruit numbers per plant 4) Fruit antioxidant contents 5) Early ripening Among the red plastic has more beneficial